(re)start in our init scripts seems broken - Mailing list pgsql-hackers

From Tomas Vondra
Subject (re)start in our init scripts seems broken
Date
Msg-id f1b181e5-8b33-807d-a276-f7cedb09e32e@2ndquadrant.com
Whole thread Raw
Responses Re: (re)start in our init scripts seems broken
List pgsql-hackers
Hi,

A few days ago I ran into a problem with the init script packaged in our 
community RPM packages. What happened was that they initiated a restart, 
but this happened:

# /etc/init.d/postgresql-9.3 restart
Stopping postgresql-9.3 service:                           [FAILED]
Starting postgresql-9.3 service:                           [  OK  ]

The database was however still in the shutdown mode, performing a 
checkpoint. Sadly the init script uses default timeout, so the stop 
terminates after just 60 seconds. But that seems fine, as the init 
script reports the failure correctly.

However the start action then seemingly succeeds, because it does this:
    echo -n "$PSQL_START"    $SU -l postgres -c "$PGENGINE/postmaster -D '$PGDATA' ${PGOPTS} &" >> "$PGLOG" 2>&1 <
/dev/null   sleep 2    pid=`head -n 1 "$PGDATA/postmaster.pid" 2>/dev/null`    if [ "x$pid" != x ]    then
success"$PSQL_START"            touch "$lockfile"            echo $pid > "$pidfile"            echo    else
failure"$PSQL_START"            echo            script_result=1    fi
 

It simply attempts to start the postmaster directly (instead of using 
pg_ctl), does not check the return code and instead proceeds to check 
the postmaster.pid file and existence of the process.

This however fails to do the trick, because the database is still 
running (in shutdown), so the postmaster does not overwrite the file. 
And of course the PID still matches a running process.

Is there a reason why it's coded like this? I think we should use the 
pg_ctl instead or (at the very least) check the postmaster return code. 
Also, perhaps we should add an explicit timeout, higher than 60 seconds.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services



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