Parameter · Reporting and Logging / Where to Log

syslog_ident

Sets the program name used to identify PostgreSQL messages in syslog.

Default: postgres
Type: string
Applies: Reload

In plain words

The program name shown in front of each syslog line, like postgres[7254]:. Change it to tell several PostgreSQL servers on one machine apart, or to route them to different files.

For DBAs and operators

Only used with syslog in log_destination. It becomes the syslog TAG (programname in rsyslog, SYSLOG_IDENTIFIER in journald), followed by the PID of the process that wrote the line. Captured after ALTER SYSTEM SET syslog_ident = 'pg-main' and a reload:

<132>Oct 22 15:40:32 pg-main[7254]: [7-1] 2026-10-22 15:40:32.551 UTC [7254] ERROR: division by zero

Route by ident:

:programname, isequal, "pg-main"   /var/log/pg-main.log
& stop

journalctl -t pg-main -f

Note that log_line_prefix is still applied, so the default %m [%p] repeats a timestamp and PID that syslog already adds. Many sites shorten the prefix for syslog, e.g. '%q%u@%d '. See also cluster_name for distinguishing clusters in ps.

How to change it

Change in postgresql.conf or ALTER SYSTEM, then run SELECT pg_reload_conf().

See it in context

Logger (logging collector)

Related parameters

log_destination syslog_facility syslog_sequence_numbers cluster_name

All Reporting and Logging parameters