Question

With a freshly installed version of Postgres 9.2 via yum repository on Centos 6, how do you run postgres as a different user when it is configured to run as ‘postgres:postgres’ (u:g) out of the box?

Answer 1

This is only for a fresh installation (as it pertained to my situation) as it involves blowing away the data dir.

The steps I took to resolve this issue while utilizing the packaged startup scripts for a fresh installation:

1. Remove the postgres data dir /var/lib/pgsql/9.2/data if you’ve already gone through the initdb process with the postgres user:group configured as default.
2. Modify the startup script (/etc/init.d/postgresql-9.2) to replace all instances of postgres:postgres with NEWUSER:NEWGROUP.
3. Modify the startup script to replace all instances of postgres in any $SU -l postgres lines with the NEWUSER.
4. run /etc/init.d/postgres initdb to regenerate the cluster using the new username
5. Make sure any logs created are owned by the new user or remove old logs if error on initdb (the configuration file in my case was found in /var/lib/pgsql/9.2/data/postgresql.conf).
6. Startup postgres and it should now be running under the new user/group.

I understand this might not be what other people are looking for if they have existing postgres db’s and want to restart the server to run as a different user/group combo – this was not my case, and I didn’t see an answer posted anywhere for a ‘fresh’ install utilizing the pre-packaged startup scripts.