My PostgreSQL server unexpectedly restarted with such messages:

2017-08-16 03:44:34 GMT LOG:  received fast shutdown request
2017-08-16 03:44:34 GMT LOG:  aborting any active transactions
2017-08-16 03:44:34 GMT FATAL:  terminating connection due to administrator command
2017-08-16 03:44:34 GMT FATAL:  terminating connection due to administrator command
2017-08-16 03:44:34 GMT LOG:  autovacuum launcher shutting down
2017-08-16 03:44:34 GMT LOG:  shutting down
2017-08-16 03:44:34 GMT LOG:  database system is shut down
2017-08-16 03:46:04 GMT LOG:  incomplete startup packet
2017-08-16 03:46:04 GMT LOG:  database system was shut down at 2017-08-16 03:44:34 GMT
2017-08-16 03:46:04 GMT LOG:  MultiXact member wraparound protections are now enabled
2017-08-16 03:46:04 GMT LOG:  database system is ready to accept connections
2017-08-16 03:46:04 GMT LOG:  autovacuum launcher started

what could be the reason?

Configuration details:

OS: Ubuntu 16.04.1 LTS (Windows Azure VM)
PostgreSQL version: 9.5.8
listen address: * (my bad, but Azure have to block another ports from external access.
                   I didn't enable PG 5432 port for external access) 
HBA config:
local   all             postgres                                ident
host    all             all               md5
host    all             all             ::1/128                 md5
host    all             all                md5
host    replication     app_replicator              md5
local   all             all                                     peer
  • Have you gone through this dba.stackexchange.com/questions/87622/… Aug 16, 2017 at 13:54
  • Thanks, I read it. But I think that only common detail between issues is "incomplete startup packet" message. It's strange message but I'm more worried about database restart. Aug 16, 2017 at 14:12
  • Did the server itself restart, or just Postgres? If the latter, did a Postgresql version upgrade occur?
    – bma
    Aug 16, 2017 at 14:54
  • Only Postgres restarted. I did't invoke postgresql update by hand if you asked about it. Aug 16, 2017 at 16:10

3 Answers 3


2017-08-16 03:44:34 GMT LOG: received fast shutdown request

Someone did a pg_ctl -m fast stop then pg_ctl start, either manually or via the Windows service controller (services.msc, net service, ...).

If it wasn't you, it was a scheduled job, automatic update for some tool related to PostgreSQL from some unofficial 3rd party, etc. Because unless your system got hit by the most mystically lucky cosmic ray in history, that's what happened.

There's no way to restart PostgreSQL from within the PostgreSQL SQL environment (a SQL connection via PgAdmin, psql, etc). You could do it by sending a signal from an untrusted procedural language like plpythonu or plperlu if you're connected as the database superuser and these languages are installed. But otherwise it'd be done at the command-shell level with pg_ctl, by signalling the postmaster process, etc.

  • Does PostgreSQL has ability to initiate its restart by himself? Aug 17, 2017 at 6:40
  • 1
    @CraigRinger I think it was probably separate pg_ctl -mf stop and pg_ctl start commands, not a single restart, based on the 1.5 minutes between them.
    – jjanes
    Aug 17, 2017 at 16:38
  • @jjanes Agreed, I misread the timestamps. Aug 18, 2017 at 1:34
  • @CraigRinger Could you incorporate your longer comment into your Answer? That's a very interesting point. Aug 18, 2017 at 6:09
  • 2
    In my case, I had a look at /var/log/apt/history.log and found that unattended-upgrade had caused the restart after an update to some postgres tools
    – omushpapa
    Aug 26, 2020 at 7:29

In my case, this happened automatically due to the system was out of memory.

Found logs about oom_reaper and dotnet oom tasks in Syslog, but not from Postgres. I only got the message "received fast shutdown request" in the Postgres csvlog.

PS: Since my Postgres is running inside of Docker i can't mutually exclude that Docker sent a signal and forced this shutdown (but I don't assume this)

  • Can I ask what version of PostgreSQL you were seeing the "fast shutdown" message? I am trying to track down if it is hardware or PostgreSQL version issue between a 5 year old and a 10 year old machine. Both have run a mix of 9.3, 12, and 14 (probably others too but those the most).
    – Kevin
    Jan 5 at 2:22

When this happened to me it was automatic updates to PostgreSQL. I validated this by looking at the /var/log/dpkg.log file and seeing that PostgreSQL was updated at the time of the shutdown.

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