PostgreSQL logs

/var/log/postgresql/

zcat -f /var/log/postgresql/* | egrep "FATAL|ERROR"
zcat -f /var/log/postgresql/postgresql-*-main.log | egrep "FATAL|ERROR"

FATAL | ERROR | LOG | HINT | DETAIL

Configuration

 show log_destination ;
 log_destination 
-----------------
 stderr
(1 row)

show syslog_facility ; 
 syslog_facility 
-----------------
 local0
(1 row)

show syslog_ident ;
 syslog_ident 
--------------
 postgres
(1 row)

Messages

FATAL: the database system is in recovery mode

ERROR: out of shared memory

ERROR:  duplicate key value violates unique constraint "YOUR_TEXT_HERE"
LOG:  autovacuum: found orphan temp table "TABLENAME"."duplicate_file_name$" in database "DATABASE_NAME"

ERROR:  duplicate key value violates unique constraint "YOUR_TEXT_HERE"
DETAIL:  Key (XXXXX, YYYYY)=(#####, -#######) already exists.
STATEMENT:  insert into ZZZZXXXSS (xx_id, yy_id, zz_value) values ($1,$2,$3)
LOG:  received smart shutdown request
LOG:  autovacuum launcher shutting down

LOG:  all server processes terminated; reinitializing
LOG:  database system was interrupted; last known up at 2020-04-15 09:03:50 UTC
LOG:  database system was not properly shut down; automatic recovery in progress
LOG:  redo starts at 5/50DC63D0
LOG:  invalid record length at 5/50EC7A60
LOG:  redo done at 5/50EC7A28
LOG:  last completed transaction was at log time 2020-04-15 09:07:19.636273+00
LOG:  MultiXact member wraparound protections are now enabled
LOG:  database system is ready to accept connections

LOG:  database system was shut down at 2022-11-22 09:14:15 UTC
LOG:  MultiXact member wraparound protections are now enabled
LOG:  autovacuum launcher started
LOG:  database system is ready to accept connections

ERROR:  could not extend file "base/16385/t17_174219": No space left on device

WARNING:  terminating connection because of crash of another server process
DETAIL:  The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.
HINT:  In a moment you should be able to reconnect to the database and repeat your command.

See also

• PostgreSQL logs, HINT