From 7b43ef34b776be1704e19c010292db6470de0940 Mon Sep 17 00:00:00 2001
From: Slavi Pantaleev <slavi@devture.com>
Date: Sun, 27 Nov 2022 09:16:18 +0200
Subject: [PATCH] Remove more hardcoded matrix-postgres references

---
 docs/importing-postgres.md                    |   4 +-
 docs/maintenance-postgres.md                  |   2 +-
 docs/updating-users-passwords.md              |   2 +-
 group_vars/matrix_servers                     | 197 ++++++++++--------
 .../matrix-backup-borg/defaults/main.yml      |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../matrix-bot-buscarron/defaults/main.yml    |   2 +-
 .../tasks/validate_config.yml                 |   9 +-
 .../matrix-bot-postmoogle/defaults/main.yml   |   2 +-
 .../tasks/validate_config.yml                 |   9 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  17 +-
 .../defaults/main.yml                         |   4 +-
 .../tasks/validate_config.yml                 |   9 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   4 +-
 .../tasks/validate_config.yml                 |  17 +-
 .../defaults/main.yml                         |   4 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  13 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  16 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  16 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  15 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  17 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/validate_config.yml                 |  12 +-
 .../custom/matrix-dimension/defaults/main.yml |   2 +-
 .../tasks/validate_config.yml                 |  10 +-
 .../custom/matrix-etherpad/defaults/main.yml  |   2 +-
 .../matrix-etherpad/tasks/validate_config.yml |  10 +-
 roles/custom/matrix-ma1sd/defaults/main.yml   |   2 +-
 .../matrix-ma1sd/tasks/validate_config.yml    |   9 +-
 .../tasks/validate_config.yml                 |   2 +-
 .../defaults/main.yml                         |   2 +-
 .../tasks/main.yml                            |   3 +
 .../tasks/validate_config.yml                 |   9 +
 .../matrix-registration/defaults/main.yml     |   2 +-
 .../tasks/validate_config.yml                 |  11 +-
 52 files changed, 294 insertions(+), 244 deletions(-)
 create mode 100644 roles/custom/matrix-prometheus-postgres-exporter/tasks/validate_config.yml

diff --git a/docs/importing-postgres.md b/docs/importing-postgres.md
index fe3817f53..a44afdcfb 100644
--- a/docs/importing-postgres.md
+++ b/docs/importing-postgres.md
@@ -97,9 +97,9 @@ Once the database is clear and the ownership of the tables has been fixed in the
 Check, if `--dbname` is set to `synapse` (not `matrix`) and replace paths (or even better, copy this line from your terminal)
 
 ```
-/usr/bin/env docker run --rm --name matrix-postgres-import --log-driver=none --user=998:1001 --cap-drop=ALL --network=matrix --env-file=/matrix/postgres/env-postgres-psql --mount type=bind,src=/migration/synapse_dump.sql,dst=/synapse_dump.sql,ro --entrypoint=/bin/sh docker.io/postgres:14.1-alpine -c "cat /synapse_dump.sql | grep -vE '^(CREATE|ALTER) ROLE (matrix)(;| WITH)' | grep -vE '^CREATE DATABASE (matrix)\s' | psql -v ON_ERROR_STOP=1 -h matrix-postgres --dbname=synapse"
+/usr/bin/env docker run --rm --name matrix-postgres-import --log-driver=none --user=998:1001 --cap-drop=ALL --network=matrix --env-file=/matrix/postgres/env-postgres-psql --mount type=bind,src=/migration/synapse_dump.sql,dst=/synapse_dump.sql,ro --entrypoint=/bin/sh docker.io/postgres:15.0-alpine -c "cat /synapse_dump.sql | grep -vE '^(CREATE|ALTER) ROLE (matrix)(;| WITH)' | grep -vE '^CREATE DATABASE (matrix)\s' | psql -v ON_ERROR_STOP=1 -h matrix-postgres --dbname=synapse"
 ```
 
 ### Hints
 
-To open psql terminal run `/usr/local/bin/matrix-postgres-cli`
+To open psql terminal run `/matrix/postgres/bin/cli`
diff --git a/docs/maintenance-postgres.md b/docs/maintenance-postgres.md
index 1b8487031..cf7f5eeb5 100644
--- a/docs/maintenance-postgres.md
+++ b/docs/maintenance-postgres.md
@@ -16,7 +16,7 @@ Table of contents:
 
 ## Getting a database terminal
 
-You can use the `/usr/local/bin/matrix-postgres-cli` tool to get interactive terminal access ([psql](https://www.postgresql.org/docs/11/app-psql.html)) to the PostgreSQL server.
+You can use the `/matrix/postgres/bin/cli` tool to get interactive terminal access ([psql](https://www.postgresql.org/docs/11/app-psql.html)) to the PostgreSQL server.
 
 If you are using an [external Postgres server](configuring-playbook-external-postgres.md), the above tool will not be available.
 
diff --git a/docs/updating-users-passwords.md b/docs/updating-users-passwords.md
index 2ea20d2f6..30aa8c99a 100644
--- a/docs/updating-users-passwords.md
+++ b/docs/updating-users-passwords.md
@@ -1,6 +1,6 @@
 # Updating users passwords
 
-## Option 1 (if you are using the default matrix-postgres container):
+## Option 1 (if you are using the integrated Postgres database):
 
 You can reset a user's password via the Ansible playbook (make sure to edit the `<your-username>` and `<your-password>` part below):
 
diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 7bc13c754..a2c245141 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -429,6 +429,7 @@ matrix_appservice_discord_homeserver_token: "{{ '%s' | format(matrix_homeserver_
 # We only make this use Postgres if our own Postgres server is enabled.
 # It's only then (for now) that we can automatically create the necessary database and user for this service.
 matrix_appservice_discord_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_appservice_discord_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_appservice_discord_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'as.discord.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -511,6 +512,7 @@ matrix_appservice_slack_systemd_required_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_appservice_slack_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'nedb' }}"
+matrix_appservice_slack_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_appservice_slack_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'as.slack.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -553,6 +555,7 @@ matrix_appservice_irc_appservice_token: "{{ '%s' | format(matrix_homeserver_gene
 matrix_appservice_irc_homeserver_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'irc.hs.token', rounds=655555) | to_uuid }}"
 
 matrix_appservice_irc_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'nedb' }}"
+matrix_appservice_irc_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_appservice_irc_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'as.irc.db', rounds=655555) | to_uuid }}"
 
 
@@ -591,6 +594,7 @@ matrix_appservice_kakaotalk_homeserver_token: "{{ '%s' | format(matrix_homeserve
 matrix_appservice_kakaotalk_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
 
 matrix_appservice_kakaotalk_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_appservice_kakaotalk_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_appservice_kakaotalk_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'as.kakao.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -630,6 +634,7 @@ matrix_beeper_linkedin_login_shared_secret: "{{ matrix_synapse_ext_password_prov
 
 matrix_beeper_linkedin_bridge_presence: "{{ matrix_synapse_presence_enabled if matrix_synapse_enabled else true }}"
 
+matrix_beeper_linkedin_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_beeper_linkedin_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maulinkedin.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -668,6 +673,7 @@ matrix_go_skype_bridge_login_shared_secret: "{{ matrix_synapse_ext_password_prov
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_go_skype_bridge_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_go_skype_bridge_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_go_skype_bridge_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'goskype.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -676,6 +682,51 @@ matrix_go_skype_bridge_database_password: "{{ '%s' | format(matrix_homeserver_ge
 #
 ######################################################################
 
+
+######################################################################
+#
+# matrix-bridge-mautrix-discord
+#
+######################################################################
+
+# We don't enable bridges by default.
+matrix_mautrix_discord_enabled: false
+
+matrix_mautrix_discord_container_image_self_build: "{{ matrix_architecture not in ['arm64', 'amd64'] }}"
+
+matrix_mautrix_discord_systemd_required_services_list: |
+  {{
+    ['docker.service']
+    +
+    ['matrix-' + matrix_homeserver_implementation + '.service']
+    +
+    ([devture_postgres_identifier ~ '.service'] if devture_postgres_enabled else [])
+    +
+    (['matrix-nginx-proxy.service'] if matrix_nginx_proxy_enabled else [])
+  }}
+
+matrix_mautrix_discord_appservice_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudisc.as.tok', rounds=655555) | to_uuid }}"
+
+matrix_mautrix_discord_homeserver_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudisc.hs.tok', rounds=655555) | to_uuid }}"
+
+matrix_mautrix_discord_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
+
+# Postgres is the default, except if not using internal Postgres server
+matrix_mautrix_discord_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_discord_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
+matrix_mautrix_discord_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudiscord.db', rounds=655555) | to_uuid }}"
+
+# Enabling bridge.restricted_rooms for this bridge does not work well with Conduit, so we disable it by default.
+# This will be fixed in the upcoming `0.5.0` release of conduit.
+matrix_mautrix_discord_bridge_restricted_rooms: "{{ false if matrix_homeserver_implementation == 'conduit' else true }}"
+
+######################################################################
+#
+# /matrix-bridge-mautrix-discord
+#
+######################################################################
+
+
 ######################################################################
 #
 # matrix-bridge-mautrix-facebook
@@ -713,6 +764,7 @@ matrix_mautrix_facebook_bridge_presence: "{{ matrix_synapse_presence_enabled if
 # We'd like to force-set people with external Postgres to SQLite, so the bridge role can complain
 # and point them to a migration path.
 matrix_mautrix_facebook_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_facebook_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_facebook_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.fb.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -722,47 +774,6 @@ matrix_mautrix_facebook_database_password: "{{ '%s' | format(matrix_homeserver_g
 ######################################################################
 
 
-######################################################################
-#
-# matrix-bridge-mautrix-hangouts
-#
-######################################################################
-
-# We don't enable bridges by default.
-matrix_mautrix_hangouts_enabled: false
-
-matrix_mautrix_hangouts_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
-
-matrix_mautrix_hangouts_systemd_required_services_list: |
-  {{
-    ['docker.service']
-    +
-    ['matrix-' + matrix_homeserver_implementation + '.service']
-    +
-    ([devture_postgres_identifier ~ '.service'] if devture_postgres_enabled else [])
-    +
-    (['matrix-nginx-proxy.service'] if matrix_nginx_proxy_enabled else [])
-  }}
-
-matrix_mautrix_hangouts_appservice_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'ho.as.token', rounds=655555) | to_uuid }}"
-
-matrix_mautrix_hangouts_homeserver_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'ho.hs.token', rounds=655555) | to_uuid }}"
-
-matrix_mautrix_hangouts_container_http_host_bind_port: "{{ '' if matrix_nginx_proxy_enabled else '127.0.0.1:9007' }}"
-
-matrix_mautrix_hangouts_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
-
-# Postgres is the default, except if not using internal Postgres server
-matrix_mautrix_hangouts_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
-matrix_mautrix_hangouts_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.hangouts.db', rounds=655555) | to_uuid }}"
-
-######################################################################
-#
-# /matrix-bridge-mautrix-hangouts
-#
-######################################################################
-
-
 ######################################################################
 #
 # matrix-bridge-mautrix-googlechat
@@ -795,6 +806,7 @@ matrix_mautrix_googlechat_login_shared_secret: "{{ matrix_synapse_ext_password_p
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_mautrix_googlechat_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_googlechat_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_googlechat_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.gc.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -804,6 +816,48 @@ matrix_mautrix_googlechat_database_password: "{{ '%s' | format(matrix_homeserver
 ######################################################################
 
 
+######################################################################
+#
+# matrix-bridge-mautrix-hangouts
+#
+######################################################################
+
+# We don't enable bridges by default.
+matrix_mautrix_hangouts_enabled: false
+
+matrix_mautrix_hangouts_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
+
+matrix_mautrix_hangouts_systemd_required_services_list: |
+  {{
+    ['docker.service']
+    +
+    ['matrix-' + matrix_homeserver_implementation + '.service']
+    +
+    ([devture_postgres_identifier ~ '.service'] if devture_postgres_enabled else [])
+    +
+    (['matrix-nginx-proxy.service'] if matrix_nginx_proxy_enabled else [])
+  }}
+
+matrix_mautrix_hangouts_appservice_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'ho.as.token', rounds=655555) | to_uuid }}"
+
+matrix_mautrix_hangouts_homeserver_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'ho.hs.token', rounds=655555) | to_uuid }}"
+
+matrix_mautrix_hangouts_container_http_host_bind_port: "{{ '' if matrix_nginx_proxy_enabled else '127.0.0.1:9007' }}"
+
+matrix_mautrix_hangouts_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
+
+# Postgres is the default, except if not using internal Postgres server
+matrix_mautrix_hangouts_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_hangouts_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
+matrix_mautrix_hangouts_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.hangouts.db', rounds=655555) | to_uuid }}"
+
+######################################################################
+#
+# /matrix-bridge-mautrix-hangouts
+#
+######################################################################
+
+
 ######################################################################
 #
 # matrix-bridge-mautrix-instagram
@@ -837,6 +891,7 @@ matrix_mautrix_instagram_bridge_presence: "{{ matrix_synapse_presence_enabled if
 # We'd like to force-set people with external Postgres to SQLite, so the bridge role can complain
 # and point them to a migration path.
 matrix_mautrix_instagram_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_instagram_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_instagram_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.ig.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -879,6 +934,7 @@ matrix_mautrix_signal_appservice_token: "{{ '%s' | format(matrix_homeserver_gene
 matrix_mautrix_signal_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
 
 matrix_mautrix_signal_database_engine: 'postgres'
+matrix_mautrix_signal_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_signal_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.signal.db', rounds=655555) | to_uuid }}"
 
 matrix_mautrix_signal_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
@@ -927,6 +983,7 @@ matrix_mautrix_telegram_login_shared_secret: "{{ matrix_synapse_ext_password_pro
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_mautrix_telegram_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_telegram_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_telegram_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mau.telegram.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -1002,6 +1059,7 @@ matrix_mautrix_whatsapp_login_shared_secret: "{{ matrix_synapse_ext_password_pro
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_mautrix_whatsapp_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_mautrix_whatsapp_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_mautrix_whatsapp_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mauwhatsapp.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -1010,48 +1068,6 @@ matrix_mautrix_whatsapp_database_password: "{{ '%s' | format(matrix_homeserver_g
 #
 ######################################################################
 
-######################################################################
-#
-# matrix-bridge-mautrix-discord
-#
-######################################################################
-
-# We don't enable bridges by default.
-matrix_mautrix_discord_enabled: false
-
-matrix_mautrix_discord_container_image_self_build: "{{ matrix_architecture not in ['arm64', 'amd64'] }}"
-
-matrix_mautrix_discord_systemd_required_services_list: |
-  {{
-    ['docker.service']
-    +
-    ['matrix-' + matrix_homeserver_implementation + '.service']
-    +
-    ([devture_postgres_identifier ~ '.service'] if devture_postgres_enabled else [])
-    +
-    (['matrix-nginx-proxy.service'] if matrix_nginx_proxy_enabled else [])
-  }}
-
-matrix_mautrix_discord_appservice_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudisc.as.tok', rounds=655555) | to_uuid }}"
-
-matrix_mautrix_discord_homeserver_token: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudisc.hs.tok', rounds=655555) | to_uuid }}"
-
-matrix_mautrix_discord_login_shared_secret: "{{ matrix_synapse_ext_password_provider_shared_secret_auth_shared_secret if matrix_synapse_ext_password_provider_shared_secret_auth_enabled else '' }}"
-
-# Postgres is the default, except if not using internal Postgres server
-matrix_mautrix_discord_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
-matrix_mautrix_discord_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'maudiscord.db', rounds=655555) | to_uuid }}"
-
-# Enabling bridge.restricted_rooms for this bridge does not work well with Conduit, so we disable it by default.
-# This will be fixed in the upcoming `0.5.0` release of conduit.
-matrix_mautrix_discord_bridge_restricted_rooms: "{{ false if matrix_homeserver_implementation == 'conduit' else true }}"
-
-######################################################################
-#
-# /matrix-bridge-mautrix-discord
-#
-######################################################################
-
 ######################################################################
 #
 # matrix-sms-bridge
@@ -1540,6 +1556,8 @@ matrix_bot_honoroit_container_image_self_build: "{{ matrix_architecture not in [
 # We don't enable bots by default.
 matrix_bot_buscarron_enabled: false
 
+matrix_bot_buscarron_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
+
 matrix_bot_buscarron_systemd_required_services_list: |
   {{
     ['docker.service']
@@ -1553,8 +1571,8 @@ matrix_bot_buscarron_systemd_required_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_bot_buscarron_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_bot_buscarron_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_bot_buscarron_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'buscarron.bot.db', rounds=655555) | to_uuid }}"
-matrix_bot_buscarron_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
 
 ######################################################################
 #
@@ -1570,6 +1588,9 @@ matrix_bot_buscarron_container_image_self_build: "{{ matrix_architecture not in
 
 # We don't enable bots by default.
 matrix_bot_postmoogle_enabled: false
+
+matrix_bot_postmoogle_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
+
 matrix_bot_postmoogle_ssl_path: "{{ matrix_ssl_config_dir_path }}"
 matrix_bot_postmoogle_tls_cert: "{% for domain in matrix_bot_postmoogle_domains %}/ssl/live/{{ domain }}/fullchain.pem {% endfor %}"
 matrix_bot_postmoogle_tls_key: "{% for domain in matrix_bot_postmoogle_domains %}/ssl/live/{{ domain }}/privkey.pem {% endfor %}"
@@ -1585,10 +1606,9 @@ matrix_bot_postmoogle_systemd_required_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_bot_postmoogle_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_bot_postmoogle_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_bot_postmoogle_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'postmoogle.db', rounds=655555) | to_uuid }}"
 
-matrix_bot_postmoogle_container_image_self_build: "{{ matrix_architecture not in ['amd64', 'arm64'] }}"
-
 ######################################################################
 #
 # /matrix-bot-postmoogle
@@ -1822,6 +1842,7 @@ matrix_dimension_systemd_required_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_dimension_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_dimension_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_dimension_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'dimension.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -1850,7 +1871,6 @@ matrix_etherpad_systemd_required_services_list: |
   }}
 
 matrix_etherpad_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
-
 matrix_etherpad_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'etherpad.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -2028,6 +2048,7 @@ matrix_ma1sd_systemd_wanted_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_ma1sd_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_ma1sd_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_ma1sd_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'ma1sd.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
@@ -2845,6 +2866,7 @@ matrix_prometheus_scraper_hookshot_targets: "{{ [matrix_hookshot_container_url |
 ######################################################################
 
 matrix_prometheus_postgres_exporter_enabled: false
+matrix_prometheus_postgres_exporter_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_prometheus_postgres_exporter_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'prometheus.pg.db', rounds=655555) | to_uuid }}"
 
 matrix_prometheus_postgres_exporter_systemd_required_services_list: |
@@ -2943,6 +2965,7 @@ matrix_registration_systemd_required_services_list: |
 
 # Postgres is the default, except if not using internal Postgres server
 matrix_registration_database_engine: "{{ 'postgres' if devture_postgres_enabled else 'sqlite' }}"
+matrix_registration_database_hostname: "{{ devture_postgres_connection_hostname if devture_postgres_enabled else '' }}"
 matrix_registration_database_password: "{{ '%s' | format(matrix_homeserver_generic_secret_key) | password_hash('sha512', 'mx.registr.db', rounds=655555) | to_uuid }}"
 
 ######################################################################
diff --git a/roles/custom/matrix-backup-borg/defaults/main.yml b/roles/custom/matrix-backup-borg/defaults/main.yml
index de086ebd9..fbeb11670 100644
--- a/roles/custom/matrix-backup-borg/defaults/main.yml
+++ b/roles/custom/matrix-backup-borg/defaults/main.yml
@@ -39,7 +39,7 @@ matrix_backup_borg_location_source_directories: []
 matrix_backup_borg_postgresql_enabled: true
 matrix_backup_borg_supported_postgres_versions: ['12', '13', '14']
 matrix_backup_borg_postgresql_databases: []
-matrix_backup_borg_postgresql_databases_hostname: "matrix-postgres"
+matrix_backup_borg_postgresql_databases_hostname: ''
 matrix_backup_borg_postgresql_databases_username: "matrix"
 matrix_backup_borg_postgresql_databases_password: ""
 matrix_backup_borg_postgresql_databases_port: 5432
diff --git a/roles/custom/matrix-backup-borg/tasks/validate_config.yml b/roles/custom/matrix-backup-borg/tasks/validate_config.yml
index 66e487dd9..bb6cd4151 100644
--- a/roles/custom/matrix-backup-borg/tasks/validate_config.yml
+++ b/roles/custom/matrix-backup-borg/tasks/validate_config.yml
@@ -1,12 +1,13 @@
 ---
-- name: Fail if required settings not defined
+- name: Fail if required backup-borg settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_backup_borg_ssh_key_private"
-    - "matrix_backup_borg_location_repositories"
+    - {'name': 'matrix_backup_borg_ssh_key_private', when: true}
+    - {'name': 'matrix_backup_borg_location_repositories', when: true}
+    - {'name': 'matrix_backup_borg_postgresql_databases_hostname', when: "{{ matrix_backup_borg_postgresql_enabled }}"}
 
 - name: Fail if encryption passphrase is undefined unless repository is unencrypted
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-bot-buscarron/defaults/main.yml b/roles/custom/matrix-bot-buscarron/defaults/main.yml
index 21d9a4a39..290248e0a 100644
--- a/roles/custom/matrix-bot-buscarron/defaults/main.yml
+++ b/roles/custom/matrix-bot-buscarron/defaults/main.yml
@@ -43,7 +43,7 @@ matrix_bot_buscarron_sqlite_database_path_in_container: "/data/bot.db"
 
 matrix_bot_buscarron_database_username: 'buscarron'
 matrix_bot_buscarron_database_password: 'some-password'
-matrix_bot_buscarron_database_hostname: 'matrix-postgres'
+matrix_bot_buscarron_database_hostname: ''
 matrix_bot_buscarron_database_port: 5432
 matrix_bot_buscarron_database_name: 'buscarron'
 
diff --git a/roles/custom/matrix-bot-buscarron/tasks/validate_config.yml b/roles/custom/matrix-bot-buscarron/tasks/validate_config.yml
index 04238012a..3547fc037 100644
--- a/roles/custom/matrix-bot-buscarron/tasks/validate_config.yml
+++ b/roles/custom/matrix-bot-buscarron/tasks/validate_config.yml
@@ -1,9 +1,10 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required Buscarron settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_bot_buscarron_password"
+    - {'name': 'matrix_bot_buscarron_password', when: true}
+    - {'name': 'matrix_bot_buscarron_database_hostname', when: "{{ matrix_bot_buscarron_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bot-postmoogle/defaults/main.yml b/roles/custom/matrix-bot-postmoogle/defaults/main.yml
index 88a712d51..24bf7cf2e 100644
--- a/roles/custom/matrix-bot-postmoogle/defaults/main.yml
+++ b/roles/custom/matrix-bot-postmoogle/defaults/main.yml
@@ -42,7 +42,7 @@ matrix_bot_postmoogle_sqlite_database_path_in_container: "/data/bot.db"
 
 matrix_bot_postmoogle_database_username: 'postmoogle'
 matrix_bot_postmoogle_database_password: 'some-password'
-matrix_bot_postmoogle_database_hostname: 'matrix-postgres'
+matrix_bot_postmoogle_database_hostname: ''
 matrix_bot_postmoogle_database_port: 5432
 matrix_bot_postmoogle_database_name: 'postmoogle'
 
diff --git a/roles/custom/matrix-bot-postmoogle/tasks/validate_config.yml b/roles/custom/matrix-bot-postmoogle/tasks/validate_config.yml
index b5d9d1ed2..1e31bd4f6 100644
--- a/roles/custom/matrix-bot-postmoogle/tasks/validate_config.yml
+++ b/roles/custom/matrix-bot-postmoogle/tasks/validate_config.yml
@@ -1,9 +1,10 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required Postmoogle settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_bot_postmoogle_password"
+    - {'name': 'matrix_bot_postmoogle_password', when: true}
+    - {'name': 'matrix_bot_postmoogle_database_hostname', when: "{{ matrix_bot_postmoogle_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-appservice-discord/defaults/main.yml b/roles/custom/matrix-bridge-appservice-discord/defaults/main.yml
index 9e061d678..ec194855e 100644
--- a/roles/custom/matrix-bridge-appservice-discord/defaults/main.yml
+++ b/roles/custom/matrix-bridge-appservice-discord/defaults/main.yml
@@ -60,7 +60,7 @@ matrix_appservice_discord_sqlite_database_path_in_container: "/data/discord.db"
 
 matrix_appservice_discord_database_username: 'matrix_appservice_discord'
 matrix_appservice_discord_database_password: 'some-password'
-matrix_appservice_discord_database_hostname: 'matrix-postgres'
+matrix_appservice_discord_database_hostname: ''
 matrix_appservice_discord_database_port: 5432
 matrix_appservice_discord_database_name: 'matrix_appservice_discord'
 
diff --git a/roles/custom/matrix-bridge-appservice-discord/tasks/validate_config.yml b/roles/custom/matrix-bridge-appservice-discord/tasks/validate_config.yml
index e005f162b..fab6a5b6e 100644
--- a/roles/custom/matrix-bridge-appservice-discord/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-appservice-discord/tasks/validate_config.yml
@@ -1,16 +1,17 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required appservice-discord settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_appservice_discord_client_id"
-    - "matrix_appservice_discord_bot_token"
-    - "matrix_appservice_discord_appservice_token"
-    - "matrix_appservice_discord_homeserver_token"
-    - "matrix_appservice_discord_homeserver_domain"
+    - {'name': 'matrix_appservice_discord_client_id', when: true}
+    - {'name': 'matrix_appservice_discord_bot_token', when: true}
+    - {'name': 'matrix_appservice_discord_appservice_token', when: true}
+    - {'name': 'matrix_appservice_discord_homeserver_token', when: true}
+    - {'name': 'matrix_appservice_discord_homeserver_domain', when: true}
+    - {'name': 'matrix_appservice_discord_database_hostname', when: "{{ matrix_appservice_discord_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed appservice-discord variables
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-bridge-appservice-irc/defaults/main.yml b/roles/custom/matrix-bridge-appservice-irc/defaults/main.yml
index d54a7685d..5e8c11910 100644
--- a/roles/custom/matrix-bridge-appservice-irc/defaults/main.yml
+++ b/roles/custom/matrix-bridge-appservice-irc/defaults/main.yml
@@ -29,8 +29,8 @@ matrix_appservice_irc_appservice_address: 'http://matrix-appservice-irc:9999'
 
 matrix_appservice_irc_database_engine: nedb
 matrix_appservice_irc_database_username: matrix_appservice_irc
-matrix_appservice_irc_database_password: ~
-matrix_appservice_irc_database_hostname: 'matrix-postgres'
+matrix_appservice_irc_database_password: 'some-password'
+matrix_appservice_irc_database_hostname: ''
 matrix_appservice_irc_database_port: 5432
 matrix_appservice_irc_database_name: matrix_appservice_irc
 
diff --git a/roles/custom/matrix-bridge-appservice-irc/tasks/validate_config.yml b/roles/custom/matrix-bridge-appservice-irc/tasks/validate_config.yml
index f0d887c8f..0c4c6c29d 100644
--- a/roles/custom/matrix-bridge-appservice-irc/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-appservice-irc/tasks/validate_config.yml
@@ -3,11 +3,12 @@
 - name: Fail if required settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_appservice_irc_appservice_token"
-    - "matrix_appservice_irc_homeserver_token"
+    - {'name': 'matrix_appservice_irc_appservice_token', when: true}
+    - {'name': 'matrix_appservice_irc_homeserver_token', when: true}
+    - {'name': 'matrix_appservice_irc_database_hostname', when: "{{ matrix_appservice_irc_database_engine == 'postgres' }}"}
 
 # Our base configuration (`matrix_appservice_irc_configuration_yaml`) is not enough to
 # let the playbook run without errors.
diff --git a/roles/custom/matrix-bridge-appservice-kakaotalk/defaults/main.yml b/roles/custom/matrix-bridge-appservice-kakaotalk/defaults/main.yml
index f27f75c55..681695073 100644
--- a/roles/custom/matrix-bridge-appservice-kakaotalk/defaults/main.yml
+++ b/roles/custom/matrix-bridge-appservice-kakaotalk/defaults/main.yml
@@ -90,7 +90,7 @@ matrix_appservice_kakaotalk_sqlite_database_path_in_container: "/data/appservice
 
 matrix_appservice_kakaotalk_database_username: 'matrix_appservice_kakaotalk'
 matrix_appservice_kakaotalk_database_password: 'some-password'
-matrix_appservice_kakaotalk_database_hostname: 'matrix-postgres'
+matrix_appservice_kakaotalk_database_hostname: ''
 matrix_appservice_kakaotalk_database_port: 5432
 matrix_appservice_kakaotalk_database_name: 'matrix_appservice_kakaotalk'
 
diff --git a/roles/custom/matrix-bridge-appservice-kakaotalk/tasks/validate_config.yml b/roles/custom/matrix-bridge-appservice-kakaotalk/tasks/validate_config.yml
index 4f838e7a5..63b173395 100644
--- a/roles/custom/matrix-bridge-appservice-kakaotalk/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-appservice-kakaotalk/tasks/validate_config.yml
@@ -1,10 +1,11 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required appservice-kakaotalk settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_appservice_kakaotalk_appservice_token"
-    - "matrix_appservice_kakaotalk_homeserver_token"
+    - {'name': 'matrix_appservice_kakaotalk_appservice_token', when: true}
+    - {'name': 'matrix_appservice_kakaotalk_homeserver_token', when: true}
+    - {'name': 'matrix_appservice_kakaotalk_database_hostname', when: "{{ matrix_appservice_kakaotalk_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-appservice-slack/defaults/main.yml b/roles/custom/matrix-bridge-appservice-slack/defaults/main.yml
index b5fbc13f9..8884edd6b 100644
--- a/roles/custom/matrix-bridge-appservice-slack/defaults/main.yml
+++ b/roles/custom/matrix-bridge-appservice-slack/defaults/main.yml
@@ -57,8 +57,8 @@ matrix_appservice_slack_id_token: ''
 
 matrix_appservice_slack_database_engine: nedb
 matrix_appservice_slack_database_username: matrix_appservice_slack
-matrix_appservice_slack_database_password: ~
-matrix_appservice_slack_database_hostname: 'matrix-postgres'
+matrix_appservice_slack_database_password: 'some-passsword'
+matrix_appservice_slack_database_hostname: ''
 matrix_appservice_slack_database_port: 5432
 matrix_appservice_slack_database_name: matrix_appservice_slack
 
diff --git a/roles/custom/matrix-bridge-appservice-slack/tasks/validate_config.yml b/roles/custom/matrix-bridge-appservice-slack/tasks/validate_config.yml
index e00eb6d4a..ef97635ec 100644
--- a/roles/custom/matrix-bridge-appservice-slack/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-appservice-slack/tasks/validate_config.yml
@@ -1,16 +1,17 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required appservice-slack settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_appservice_slack_control_room_id"
-    - "matrix_appservice_slack_appservice_token"
-    - "matrix_appservice_slack_homeserver_url"
-    - "matrix_appservice_slack_homeserver_token"
-    - "matrix_appservice_slack_id_token"
+    - {'name': 'matrix_appservice_slack_control_room_id', when: true}
+    - {'name': 'matrix_appservice_slack_appservice_token', when: true}
+    - {'name': 'matrix_appservice_slack_homeserver_url', when: true}
+    - {'name': 'matrix_appservice_slack_homeserver_token', when: true}
+    - {'name': 'matrix_appservice_slack_id_token', when: true}
+    - {'name': 'matrix_appservice_slack_database_hostname', when: "{{ matrix_appservice_slack_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed settings
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-bridge-beeper-linkedin/defaults/main.yml b/roles/custom/matrix-bridge-beeper-linkedin/defaults/main.yml
index 4f3d554b3..92d9b2e18 100644
--- a/roles/custom/matrix-bridge-beeper-linkedin/defaults/main.yml
+++ b/roles/custom/matrix-bridge-beeper-linkedin/defaults/main.yml
@@ -55,8 +55,8 @@ matrix_beeper_linkedin_appservice_bot_username: linkedinbot
 matrix_beeper_linkedin_database_engine: "postgres"
 
 matrix_beeper_linkedin_database_username: 'matrix_beeper_linkedin'
-matrix_beeper_linkedin_database_password: ""
-matrix_beeper_linkedin_database_hostname: 'matrix-postgres'
+matrix_beeper_linkedin_database_password: 'some-password'
+matrix_beeper_linkedin_database_hostname: ''
 matrix_beeper_linkedin_database_port: 5432
 matrix_beeper_linkedin_database_name: 'matrix_beeper_linkedin'
 
diff --git a/roles/custom/matrix-bridge-beeper-linkedin/tasks/validate_config.yml b/roles/custom/matrix-bridge-beeper-linkedin/tasks/validate_config.yml
index 61489b7c6..59d56ca85 100644
--- a/roles/custom/matrix-bridge-beeper-linkedin/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-beeper-linkedin/tasks/validate_config.yml
@@ -1,10 +1,11 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required beeper-linkedin settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_beeper_linkedin_appservice_token"
-    - "matrix_beeper_linkedin_homeserver_token"
+    - {'name': 'matrix_beeper_linkedin_appservice_token', when: true}
+    - {'name': 'matrix_beeper_linkedin_homeserver_token', when: true}
+    - {'name': 'matrix_beeper_linkedin_database_hostname', when: "{{ matrix_beeper_linkedin_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-go-skype-bridge/defaults/main.yml b/roles/custom/matrix-bridge-go-skype-bridge/defaults/main.yml
index a6f7aa9d3..e3cdea4bb 100644
--- a/roles/custom/matrix-bridge-go-skype-bridge/defaults/main.yml
+++ b/roles/custom/matrix-bridge-go-skype-bridge/defaults/main.yml
@@ -56,7 +56,7 @@ matrix_go_skype_bridge_sqlite_database_path_in_container: "/data/go-skype-bridge
 
 matrix_go_skype_bridge_database_username: 'matrix_go_skype_bridge'
 matrix_go_skype_bridge_database_password: 'some-password'
-matrix_go_skype_bridge_database_hostname: 'matrix-postgres'
+matrix_go_skype_bridge_database_hostname: ''
 matrix_go_skype_bridge_database_port: 5432
 matrix_go_skype_bridge_database_name: 'matrix_go_skype_bridge'
 
diff --git a/roles/custom/matrix-bridge-go-skype-bridge/tasks/validate_config.yml b/roles/custom/matrix-bridge-go-skype-bridge/tasks/validate_config.yml
index d681299f2..c9b3c2ffd 100644
--- a/roles/custom/matrix-bridge-go-skype-bridge/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-go-skype-bridge/tasks/validate_config.yml
@@ -1,10 +1,11 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required go-skype-bridge settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_go_skype_bridge_appservice_token"
-    - "matrix_go_skype_bridge_homeserver_token"
+    - {'name': 'matrix_go_skype_bridge_appservice_token', when: true}
+    - {'name': 'matrix_go_skype_bridge_homeserver_token', when: true}
+    - {'name': 'matrix_go_skype_bridge_database_hostname', when: "{{ matrix_go_skype_bridge_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-discord/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-discord/defaults/main.yml
index 7163954a4..bb8846f5f 100644
--- a/roles/custom/matrix-bridge-mautrix-discord/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-discord/defaults/main.yml
@@ -67,7 +67,7 @@ matrix_mautrix_discord_sqlite_database_path_in_container: "/data/mautrix-discord
 
 matrix_mautrix_discord_database_username: 'matrix_mautrix_discord'
 matrix_mautrix_discord_database_password: 'some-password'
-matrix_mautrix_discord_database_hostname: 'matrix-postgres'
+matrix_mautrix_discord_database_hostname: ''
 matrix_mautrix_discord_database_port: 5432
 matrix_mautrix_discord_database_name: 'matrix_mautrix_discord'
 
diff --git a/roles/custom/matrix-bridge-mautrix-discord/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-discord/tasks/validate_config.yml
index 4ba7e1270..8f4fe29e4 100644
--- a/roles/custom/matrix-bridge-mautrix-discord/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-discord/tasks/validate_config.yml
@@ -1,10 +1,11 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-discord settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_discord_appservice_token"
-    - "matrix_mautrix_discord_homeserver_token"
+    - {'name': 'matrix_mautrix_discord_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_discord_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_discord_database_hostname', when: "{{ matrix_mautrix_discord_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-facebook/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-facebook/defaults/main.yml
index e19fa9deb..989720140 100644
--- a/roles/custom/matrix-bridge-mautrix-facebook/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-facebook/defaults/main.yml
@@ -74,7 +74,7 @@ matrix_mautrix_facebook_sqlite_database_path_in_container: "/data/mautrix-facebo
 
 matrix_mautrix_facebook_database_username: 'matrix_mautrix_facebook'
 matrix_mautrix_facebook_database_password: 'some-password'
-matrix_mautrix_facebook_database_hostname: 'matrix-postgres'
+matrix_mautrix_facebook_database_hostname: ''
 matrix_mautrix_facebook_database_port: 5432
 matrix_mautrix_facebook_database_name: 'matrix_mautrix_facebook'
 
diff --git a/roles/custom/matrix-bridge-mautrix-facebook/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-facebook/tasks/validate_config.yml
index 04e45c319..d61981a67 100644
--- a/roles/custom/matrix-bridge-mautrix-facebook/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-facebook/tasks/validate_config.yml
@@ -1,14 +1,15 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-facebook settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_facebook_public_endpoint"
-    - "matrix_mautrix_facebook_appservice_token"
-    - "matrix_mautrix_facebook_homeserver_token"
+    - {'name': 'matrix_mautrix_facebook_public_endpoint', when: true}
+    - {'name': 'matrix_mautrix_facebook_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_facebook_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_facebook_database_hostname', when: "{{ matrix_mautrix_facebook_database_engine == 'postgres' }}"}
 
 - when: "matrix_mautrix_facebook_database_engine == 'sqlite' and matrix_mautrix_facebook_docker_image.endswith(':da1b4ec596e334325a1589e70829dea46e73064b')"
   block:
diff --git a/roles/custom/matrix-bridge-mautrix-googlechat/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-googlechat/defaults/main.yml
index 9c2d97b2a..f432cc637 100644
--- a/roles/custom/matrix-bridge-mautrix-googlechat/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-googlechat/defaults/main.yml
@@ -68,7 +68,7 @@ matrix_mautrix_googlechat_sqlite_database_path_in_container: "/data/mautrix-goog
 
 matrix_mautrix_googlechat_database_username: 'matrix_mautrix_googlechat'
 matrix_mautrix_googlechat_database_password: 'some-password'
-matrix_mautrix_googlechat_database_hostname: 'matrix-postgres'
+matrix_mautrix_googlechat_database_hostname: ''
 matrix_mautrix_googlechat_database_port: 5432
 matrix_mautrix_googlechat_database_name: 'matrix_mautrix_googlechat'
 
diff --git a/roles/custom/matrix-bridge-mautrix-googlechat/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-googlechat/tasks/validate_config.yml
index fc36472eb..06cb8de76 100644
--- a/roles/custom/matrix-bridge-mautrix-googlechat/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-googlechat/tasks/validate_config.yml
@@ -1,14 +1,12 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-googlechat settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_googlechat_public_endpoint"
-    - "matrix_mautrix_googlechat_appservice_token"
-    - "matrix_mautrix_googlechat_homeserver_token"
-- ansible.builtin.debug:
-    msg:
-      - '`matrix_mautrix_googlechat_homeserver_domain` == {{ matrix_mautrix_googlechat_homeserver_domain }}'
+    - {'name': 'matrix_mautrix_googlechat_public_endpoint', when: true}
+    - {'name': 'matrix_mautrix_googlechat_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_googlechat_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_googlechat_database_hostname', when: "{{ matrix_mautrix_googlechat_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-hangouts/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-hangouts/defaults/main.yml
index 8b338fd76..27f3e5930 100644
--- a/roles/custom/matrix-bridge-mautrix-hangouts/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-hangouts/defaults/main.yml
@@ -65,7 +65,7 @@ matrix_mautrix_hangouts_sqlite_database_path_in_container: "/data/mautrix-hangou
 
 matrix_mautrix_hangouts_database_username: 'matrix_mautrix_hangouts'
 matrix_mautrix_hangouts_database_password: 'some-password'
-matrix_mautrix_hangouts_database_hostname: 'matrix-postgres'
+matrix_mautrix_hangouts_database_hostname: ''
 matrix_mautrix_hangouts_database_port: 5432
 matrix_mautrix_hangouts_database_name: 'matrix_mautrix_hangouts'
 
diff --git a/roles/custom/matrix-bridge-mautrix-hangouts/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-hangouts/tasks/validate_config.yml
index c80586e09..11635642c 100644
--- a/roles/custom/matrix-bridge-mautrix-hangouts/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-hangouts/tasks/validate_config.yml
@@ -1,14 +1,12 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-hangouts settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_hangouts_public_endpoint"
-    - "matrix_mautrix_hangouts_appservice_token"
-    - "matrix_mautrix_hangouts_homeserver_token"
-- ansible.builtin.debug:
-    msg:
-      - '`matrix_mautrix_hangouts_homeserver_domain` == {{ matrix_mautrix_hangouts_homeserver_domain }}'
+    - {'name': 'matrix_mautrix_hangouts_public_endpoint', when: true}
+    - {'name': 'matrix_mautrix_hangouts_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_hangouts_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_hangouts_database_hostname', when: "{{ matrix_mautrix_hangouts_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-instagram/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-instagram/defaults/main.yml
index dcdf6723d..75b996562 100644
--- a/roles/custom/matrix-bridge-mautrix-instagram/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-instagram/defaults/main.yml
@@ -55,7 +55,7 @@ matrix_mautrix_instagram_database_engine: 'postgres'
 
 matrix_mautrix_instagram_database_username: 'matrix_mautrix_instagram'
 matrix_mautrix_instagram_database_password: 'some-password'
-matrix_mautrix_instagram_database_hostname: 'matrix-postgres'
+matrix_mautrix_instagram_database_hostname: ''
 matrix_mautrix_instagram_database_port: 5432
 matrix_mautrix_instagram_database_name: 'matrix_mautrix_instagram'
 
diff --git a/roles/custom/matrix-bridge-mautrix-instagram/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-instagram/tasks/validate_config.yml
index 99f7b0156..51bedf683 100644
--- a/roles/custom/matrix-bridge-mautrix-instagram/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-instagram/tasks/validate_config.yml
@@ -1,9 +1,10 @@
 ---
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-instagram settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_instagram_appservice_token"
-    - "matrix_mautrix_instagram_homeserver_token"
+    - {'name': 'matrix_mautrix_instagram_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_instagram_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_instagram_database_hostname', when: "{{ matrix_mautrix_instagram_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-signal/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-signal/defaults/main.yml
index 24ba9b39d..736c45575 100644
--- a/roles/custom/matrix-bridge-mautrix-signal/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-signal/defaults/main.yml
@@ -76,7 +76,7 @@ matrix_mautrix_signal_database_engine: 'postgres'
 
 matrix_mautrix_signal_database_username: 'matrix_mautrix_signal'
 matrix_mautrix_signal_database_password: 'some-password'
-matrix_mautrix_signal_database_hostname: 'matrix-postgres'
+matrix_mautrix_signal_database_hostname: ''
 matrix_mautrix_signal_database_port: 5432
 matrix_mautrix_signal_database_name: 'matrix_mautrix_signal'
 
diff --git a/roles/custom/matrix-bridge-mautrix-signal/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-signal/tasks/validate_config.yml
index ea2c1c430..5cabf18c5 100644
--- a/roles/custom/matrix-bridge-mautrix-signal/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-signal/tasks/validate_config.yml
@@ -1,15 +1,16 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-signal settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_signal_homeserver_domain"
-    - "matrix_mautrix_signal_homeserver_address"
-    - "matrix_mautrix_signal_homeserver_token"
-    - "matrix_mautrix_signal_appservice_token"
+    - {'name': 'matrix_mautrix_signal_homeserver_domain', when: true}
+    - {'name': 'matrix_mautrix_signal_homeserver_address', when: true}
+    - {'name': 'matrix_mautrix_signal_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_signal_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_signal_database_hostname', when: "{{ matrix_mautrix_signal_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Fail if matrix_mautrix_signal_bridge_permissions specified as YAML string, instead of a dictionary
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-bridge-mautrix-telegram/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-telegram/defaults/main.yml
index 6f2137e47..5d2c0c88c 100644
--- a/roles/custom/matrix-bridge-mautrix-telegram/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-telegram/defaults/main.yml
@@ -95,7 +95,7 @@ matrix_mautrix_telegram_sqlite_database_path_in_container: "/data/mautrix-telegr
 
 matrix_mautrix_telegram_database_username: 'matrix_mautrix_telegram'
 matrix_mautrix_telegram_database_password: 'some-password'
-matrix_mautrix_telegram_database_hostname: 'matrix-postgres'
+matrix_mautrix_telegram_database_hostname: ''
 matrix_mautrix_telegram_database_port: 5432
 matrix_mautrix_telegram_database_name: 'matrix_mautrix_telegram'
 
diff --git a/roles/custom/matrix-bridge-mautrix-telegram/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-telegram/tasks/validate_config.yml
index 9711448bf..16ebf37dc 100644
--- a/roles/custom/matrix-bridge-mautrix-telegram/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-telegram/tasks/validate_config.yml
@@ -1,16 +1,17 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-telegram settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_telegram_api_id"
-    - "matrix_mautrix_telegram_api_hash"
-    - "matrix_mautrix_telegram_public_endpoint"
-    - "matrix_mautrix_telegram_appservice_token"
-    - "matrix_mautrix_telegram_homeserver_token"
+    - {'name': 'matrix_mautrix_telegram_api_id', when: true}
+    - {'name': 'matrix_mautrix_telegram_api_hash', when: true}
+    - {'name': 'matrix_mautrix_telegram_public_endpoint', when: true}
+    - {'name': 'matrix_mautrix_telegram_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_telegram_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_telegram_database_hostname', when: "{{ matrix_mautrix_telegram_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed Telegram variables
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-bridge-mautrix-twitter/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-twitter/defaults/main.yml
index 684b889ac..22475596a 100644
--- a/roles/custom/matrix-bridge-mautrix-twitter/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-twitter/defaults/main.yml
@@ -54,7 +54,7 @@ matrix_mautrix_twitter_federate_rooms: true
 matrix_mautrix_twitter_database_engine: 'postgres'
 
 matrix_mautrix_twitter_database_username: 'matrix_mautrix_twitter'
-matrix_mautrix_twitter_database_password: ''
+matrix_mautrix_twitter_database_password: 'some-password'
 matrix_mautrix_twitter_database_hostname: ''
 matrix_mautrix_twitter_database_port: 5432
 matrix_mautrix_twitter_database_name: 'matrix_mautrix_twitter'
diff --git a/roles/custom/matrix-bridge-mautrix-twitter/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-twitter/tasks/validate_config.yml
index a97d292f2..cfd408a7b 100644
--- a/roles/custom/matrix-bridge-mautrix-twitter/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-twitter/tasks/validate_config.yml
@@ -3,10 +3,9 @@
 - name: Fail if required mautrix-twitter settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_twitter_appservice_token"
-    - "matrix_mautrix_twitter_homeserver_token"
-    - "matrix_mautrix_twitter_database_hostname"
-    - "matrix_mautrix_twitter_database_password"
+    - {'name': 'matrix_mautrix_twitter_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_twitter_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_twitter_database_hostname', when: "{{ matrix_mautrix_twitter_database_engine == 'postgres' }}"}
diff --git a/roles/custom/matrix-bridge-mautrix-whatsapp/defaults/main.yml b/roles/custom/matrix-bridge-mautrix-whatsapp/defaults/main.yml
index 7c923b065..186c62970 100644
--- a/roles/custom/matrix-bridge-mautrix-whatsapp/defaults/main.yml
+++ b/roles/custom/matrix-bridge-mautrix-whatsapp/defaults/main.yml
@@ -61,7 +61,7 @@ matrix_mautrix_whatsapp_sqlite_database_path_in_container: "/data/mautrix-whatsa
 
 matrix_mautrix_whatsapp_database_username: 'matrix_mautrix_whatsapp'
 matrix_mautrix_whatsapp_database_password: 'some-password'
-matrix_mautrix_whatsapp_database_hostname: 'matrix-postgres'
+matrix_mautrix_whatsapp_database_hostname: ''
 matrix_mautrix_whatsapp_database_port: 5432
 matrix_mautrix_whatsapp_database_name: 'matrix_mautrix_whatsapp'
 
diff --git a/roles/custom/matrix-bridge-mautrix-whatsapp/tasks/validate_config.yml b/roles/custom/matrix-bridge-mautrix-whatsapp/tasks/validate_config.yml
index 863dc926f..0a6a38cd7 100644
--- a/roles/custom/matrix-bridge-mautrix-whatsapp/tasks/validate_config.yml
+++ b/roles/custom/matrix-bridge-mautrix-whatsapp/tasks/validate_config.yml
@@ -1,14 +1,14 @@
 ---
 
-- name: Fail if required settings not defined
+- name: Fail if required mautrix-whatsapp settings not defined
   ansible.builtin.fail:
     msg: >-
-      You need to define a required configuration setting (`{{ item }}`).
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_mautrix_whatsapp_appservice_token"
-    - "matrix_mautrix_whatsapp_homeserver_token"
-
+    - {'name': 'matrix_mautrix_whatsapp_appservice_token', when: true}
+    - {'name': 'matrix_mautrix_whatsapp_homeserver_token', when: true}
+    - {'name': 'matrix_mautrix_whatsapp_database_hostname', when: "{{ matrix_mautrix_whatsapp_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed settings
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-dimension/defaults/main.yml b/roles/custom/matrix-dimension/defaults/main.yml
index ea1dde108..4be76fd1e 100644
--- a/roles/custom/matrix-dimension/defaults/main.yml
+++ b/roles/custom/matrix-dimension/defaults/main.yml
@@ -65,7 +65,7 @@ matrix_dimension_sqlite_database_path_in_container: "dimension.db"
 
 matrix_dimension_database_username: 'matrix_dimension'
 matrix_dimension_database_password: 'some-password'
-matrix_dimension_database_hostname: 'matrix-postgres'
+matrix_dimension_database_hostname: ''
 matrix_dimension_database_port: 5432
 matrix_dimension_database_name: 'matrix_dimension'
 
diff --git a/roles/custom/matrix-dimension/tasks/validate_config.yml b/roles/custom/matrix-dimension/tasks/validate_config.yml
index 5af0ba6d6..8f681e082 100644
--- a/roles/custom/matrix-dimension/tasks/validate_config.yml
+++ b/roles/custom/matrix-dimension/tasks/validate_config.yml
@@ -1,11 +1,13 @@
 ---
+
 - name: Fail if required Dimension settings not defined
   ansible.builtin.fail:
-    msg: >-
-      You need to define a required configuration setting (`{{ item }}`) for using Dimension.
+    msg: >
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_dimension_access_token"
-  when: "matrix_dimension_enabled and vars[item] == ''"
+    - {'name': 'matrix_dimension_access_token', when: true}
+    - {'name': 'matrix_dimension_database_hostname', when: "{{ matrix_dimension_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed Dimension variables
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-etherpad/defaults/main.yml b/roles/custom/matrix-etherpad/defaults/main.yml
index 540b2a518..874e9a300 100644
--- a/roles/custom/matrix-etherpad/defaults/main.yml
+++ b/roles/custom/matrix-etherpad/defaults/main.yml
@@ -45,7 +45,7 @@ matrix_etherpad_database_engine: 'postgres'
 
 matrix_etherpad_database_username: 'matrix_etherpad'
 matrix_etherpad_database_password: 'some-password'
-matrix_etherpad_database_hostname: 'matrix-postgres'
+matrix_etherpad_database_hostname: ''
 matrix_etherpad_database_port: 5432
 matrix_etherpad_database_name: 'matrix_etherpad'
 
diff --git a/roles/custom/matrix-etherpad/tasks/validate_config.yml b/roles/custom/matrix-etherpad/tasks/validate_config.yml
index 646648945..2bc773a63 100644
--- a/roles/custom/matrix-etherpad/tasks/validate_config.yml
+++ b/roles/custom/matrix-etherpad/tasks/validate_config.yml
@@ -1,10 +1,12 @@
 ---
 
-- name: Fail if no database is configured for Etherpad
+- name: Fail if required Etherpad settings not defined
   ansible.builtin.fail:
-    msg: >-
-      Etherpad requires a dedicated Postgres database. Please enable the built in one, or configure an external DB by redefining "matrix_etherpad_database_hostname"
-  when: matrix_etherpad_database_hostname == ''
+    msg: >
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
+  with_items:
+    - {'name': 'matrix_etherpad_database_hostname', when: true}
 
 - name: Fail if wrong mode selected
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-ma1sd/defaults/main.yml b/roles/custom/matrix-ma1sd/defaults/main.yml
index a606d0d6e..9dc32ce7b 100644
--- a/roles/custom/matrix-ma1sd/defaults/main.yml
+++ b/roles/custom/matrix-ma1sd/defaults/main.yml
@@ -64,7 +64,7 @@ matrix_ma1sd_sqlite_database_path_in_container: "/var/ma1sd/ma1sd.db"
 
 matrix_ma1sd_database_username: 'matrix_ma1sd'
 matrix_ma1sd_database_password: 'some-password'
-matrix_ma1sd_database_hostname: 'matrix-postgres'
+matrix_ma1sd_database_hostname: ''
 matrix_ma1sd_database_port: 5432
 matrix_ma1sd_database_name: 'matrix_ma1sd'
 
diff --git a/roles/custom/matrix-ma1sd/tasks/validate_config.yml b/roles/custom/matrix-ma1sd/tasks/validate_config.yml
index af12dd3f1..b490a5c62 100644
--- a/roles/custom/matrix-ma1sd/tasks/validate_config.yml
+++ b/roles/custom/matrix-ma1sd/tasks/validate_config.yml
@@ -42,11 +42,12 @@
 - name: Fail if required ma1sd settings not defined
   ansible.builtin.fail:
     msg: >
-      You need to define a required configuration setting (`{{ item }}`) for using ma1sd.
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_ma1sd_threepid_medium_email_connectors_smtp_host"
-    - "matrix_ma1sd_dns_overwrite_homeserver_client_value"
+    - {'name': 'matrix_ma1sd_threepid_medium_email_connectors_smtp_host', when: true}
+    - {'name': 'matrix_ma1sd_dns_overwrite_homeserver_client_value', when: true}
+    - {'name': 'matrix_ma1sd_database_hostname', when: "{{ matrix_ma1sd_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed ma1sd variables
   ansible.builtin.fail:
diff --git a/roles/custom/matrix-postgres-backup/tasks/validate_config.yml b/roles/custom/matrix-postgres-backup/tasks/validate_config.yml
index aab68eafa..285328c23 100644
--- a/roles/custom/matrix-postgres-backup/tasks/validate_config.yml
+++ b/roles/custom/matrix-postgres-backup/tasks/validate_config.yml
@@ -1,6 +1,6 @@
 ---
 
-- name: Fail if required Postgres settings not defined
+- name: Fail if required postgres-backup settings not defined
   ansible.builtin.fail:
     msg: >-
       You need to define a required configuration setting (`{{ item }}`).
diff --git a/roles/custom/matrix-prometheus-postgres-exporter/defaults/main.yml b/roles/custom/matrix-prometheus-postgres-exporter/defaults/main.yml
index f0cbfede9..5fc8e9196 100644
--- a/roles/custom/matrix-prometheus-postgres-exporter/defaults/main.yml
+++ b/roles/custom/matrix-prometheus-postgres-exporter/defaults/main.yml
@@ -24,7 +24,7 @@ matrix_prometheus_postgres_exporter_systemd_wanted_services_list: []
 # details for connecting to the database
 matrix_prometheus_postgres_exporter_database_username: 'matrix_prometheus_postgres_exporter'
 matrix_prometheus_postgres_exporter_database_password: 'some-password'
-matrix_prometheus_postgres_exporter_database_hostname: 'matrix-postgres'
+matrix_prometheus_postgres_exporter_database_hostname: ''
 matrix_prometheus_postgres_exporter_database_port: 5432
 matrix_prometheus_postgres_exporter_database_name: 'matrix_prometheus_postgres_exporter'
 
diff --git a/roles/custom/matrix-prometheus-postgres-exporter/tasks/main.yml b/roles/custom/matrix-prometheus-postgres-exporter/tasks/main.yml
index 2cea06049..7ff6d15ae 100644
--- a/roles/custom/matrix-prometheus-postgres-exporter/tasks/main.yml
+++ b/roles/custom/matrix-prometheus-postgres-exporter/tasks/main.yml
@@ -10,6 +10,9 @@
     - install-nginx-proxy
 
 - block:
+    - when: matrix_prometheus_postgres_exporter_enabled | bool
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/validate_config.yml"
+
     - when: matrix_prometheus_postgres_exporter_enabled | bool
       ansible.builtin.include_tasks: "{{ role_path }}/tasks/setup_install.yml"
   tags:
diff --git a/roles/custom/matrix-prometheus-postgres-exporter/tasks/validate_config.yml b/roles/custom/matrix-prometheus-postgres-exporter/tasks/validate_config.yml
new file mode 100644
index 000000000..6acf784f2
--- /dev/null
+++ b/roles/custom/matrix-prometheus-postgres-exporter/tasks/validate_config.yml
@@ -0,0 +1,9 @@
+---
+
+- name: Fail if required prometheus-postgres-exporter settings not defined
+  ansible.builtin.fail:
+    msg: >
+      You need to define a required configuration setting (`{{ item }}`).
+  when: "vars[item] == ''"
+  with_items:
+    - matrix_prometheus_postgres_exporter_database_hostname
diff --git a/roles/custom/matrix-registration/defaults/main.yml b/roles/custom/matrix-registration/defaults/main.yml
index 1e53ae982..c7a45fad0 100644
--- a/roles/custom/matrix-registration/defaults/main.yml
+++ b/roles/custom/matrix-registration/defaults/main.yml
@@ -52,7 +52,7 @@ matrix_registration_sqlite_database_path_in_container: "/data/db.sqlite3"
 
 matrix_registration_database_username: 'matrix_registration'
 matrix_registration_database_password: 'some-password'
-matrix_registration_database_hostname: 'matrix-postgres'
+matrix_registration_database_hostname: ''
 matrix_registration_database_port: 5432
 matrix_registration_database_name: 'matrix_registration'
 
diff --git a/roles/custom/matrix-registration/tasks/validate_config.yml b/roles/custom/matrix-registration/tasks/validate_config.yml
index eb140d31e..167c7c5c7 100644
--- a/roles/custom/matrix-registration/tasks/validate_config.yml
+++ b/roles/custom/matrix-registration/tasks/validate_config.yml
@@ -3,12 +3,13 @@
 - name: Fail if required matrix-registration settings not defined
   ansible.builtin.fail:
     msg: >
-      You need to define a required configuration setting (`{{ item }}`) for using matrix-registration.
-  when: "vars[item] == ''"
+      You need to define a required configuration setting (`{{ item.name }}`).
+  when: "item.when | bool and vars[item.name] == ''"
   with_items:
-    - "matrix_registration_shared_secret"
-    - "matrix_registration_admin_secret"
-    - "matrix_registration_server_location"
+    - {'name': 'matrix_registration_shared_secret', when: true}
+    - {'name': 'matrix_registration_admin_secret', when: true}
+    - {'name': 'matrix_registration_server_location', when: true}
+    - {'name': 'matrix_registration_database_hostname', when: "{{ matrix_registration_database_engine == 'postgres' }}"}
 
 - name: (Deprecation) Catch and report renamed settings
   ansible.builtin.fail: