Thread: Pg_ctl promote -- wait for slave to be promoted fully ?
Should we consider if we can make "pg_ctl -w" work for "promote" as well? The main problem is, I guess, that it can't log in - so wed' need something like "PQping()" that actually checked if it was master or slave? //Magnus ---------- Forwarded message ---------- From: Manoj Govindassamy <manoj@nimblestorage.com> Date: Fri, Jul 20, 2012 at 9:28 PM Subject: [GENERAL] Pg_ctl promote -- wait for slave to be promoted fully ? To: pgsql-general@postgresql.org Hi team, I am using PG 9.1.2 and I am promoting a slave to master with the following command. pg_ctl promote -D /pat/to/data Command does return back faster with code 0 ( = success). I assumed the slave is now the master and issued write operations. But the statement failed as the DB complained that it can do only read operation. Postgres.log showed "ready to accept connection" a second later after I issued the statement. So, my understanding is "pg_ctl promote" is triggering a slave promote and is "asynchornous". -- Anyway I can query the state of DB to know its status slave or master ?? So, that i can issue write statements only after I know that the DB is the new master now -- Or anyway to make pg_ctl promote to wait till the slave is completely promoted ? Any help is appreciated. -- thanks, Manoj -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general -- Magnus HaganderMe: http://www.hagander.net/Work: http://www.redpill-linpro.com/
On Tue, Aug 7, 2012 at 10:22 PM, Magnus Hagander <magnus@hagander.net> wrote: > Should we consider if we can make "pg_ctl -w" work for "promote" as well? +1 > The main problem is, I guess, that it can't log in - so wed' need > something like "PQping()" that actually checked if it was master or > slave? Yes. Regards, -- Fujii Masao
On Tue, Aug 7, 2012 at 1:09 PM, Fujii Masao <masao.fujii@gmail.com> wrote: > On Tue, Aug 7, 2012 at 10:22 PM, Magnus Hagander <magnus@hagander.net> wrote: >> Should we consider if we can make "pg_ctl -w" work for "promote" as well? > > +1 > >> The main problem is, I guess, that it can't log in - so wed' need >> something like "PQping()" that actually checked if it was master or >> slave? > > Yes. Is there a security concern with exposing this information to people who haven't authenticated? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company