Troubleshooting·PostgreSQL
PostgreSQL Configuration Precedence
`pg_settings.source` names where every live value came from - default, configuration file, or a session override. It is the query that ends an argument about why a setting is what it is.
Configuration Guide 15 of 47 Advanced
- OSUbuntu 26.04 LTS (resolute)
- PostgreSQL18.6-0ubuntu0.26.04.1
- PackagingDebian cluster layout
- TimeAbout 13 min
- Reviewed27 August 2026
Written against the versions above. `sourcefile` and `sourceline` are visible only to superusers and roles granted `pg_read_all_settings`. As an ordinary role they come back empty, which is a restriction rather than a bug.
| Server Name | IP Address | OS | Roles | CPU | RAM | HDD |
|---|---|---|---|---|---|---|
| db-a01 | 192.168.0.81 | Ubuntu 26.04 LTS | Primary / Source / Replica Set Member 1 | 2 Core | 4 GB | 50 GB |
Before you start
- Settings changed by the previous guides in this track.
-
Ask where each value came from
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Hand a setting back to the defaults