On 10:44 Sun 18 Mar , Jeff Ross wrote: > Hi, > > Is there a simple way to determine with a shell script if PostgreSQL is > ready to accept connections? > > PostgreSQL is started and controlled by daemontools. This shell script > is called by the /etc/netstart script as a part of bringing up the > first interface. Unfortunately, it will never exit the loop. > > #!/bin/sh > /bin/csh -cf '/command/svscanboot &' > until [ -S /tmp/.s.PGSQL.5432 ] ; do > /bin/echo "Waiting for PostgreSQL to start..." > /bin/sleep 1 > done > > Because this is happening at startup before I get a login prompt I'm not > sure I know how to figure out why it never exits the loop. > > The purpose of this is that I'm running pglogd, a daemon that uses a > custom log format and a fifo to stuff Apache web logs into a table. The > pglogd daemon must start after PostgreSQL and before Apache. I can do > this in /etc/rc.local, but OpenBSD's /etc/rc wants to start Apache > before rc.local is parsed. Once I know that PostgreSQL is up and > accepting connections I can then start pglogd and then it's ready to go > when Apache starts. > > As a side note, the original creator and maintainer of pglogd has EOLed > the project but it works well for me under 8.2.3. I intend to fix a few > of its problems (it does fine until the backend goes away ;-) and > re-release it. > > Thanks, > > Jeff Ross > > P.S. Apologies to the owner of the list--I inadvertently sent this to > the wrong address first. > > ---------------------------(end of broadcast)--------------------------- > TIP 3: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faq variants on the following might be useful... $ psql -U postgres -t -c "select pg_postmaster_start_time()" postgres` 2007-03-18 16:51:55.239342-04 so ... start loop response=`psql -U postgres -t -c "select pg_postmaster_start_time()" postgres` or response=`psql -U postgres -t -c "select now()" postgres` if [ $? == 0 ]; then parse/evaluate response to make determination of whether db is up ( or, base decision on evaluation of $? ) break loop if db is up or other criteria are met ( taking too long, etc ) else query failed, backend not ready, continue loop fi end loop
