On Thu, 9 Feb 2017 18:27:30 +0000 Rakesh Kumar <rakeshkumar464@xxxxxxxxxxx> wrote: > >Sure, but when you are doing a switchover, the standby is supposed to be > >connected to the master when you shutdown the master. So based on the doc, > >the standby should receive **everything** from the master before the master > >actually shutdown. > > We use 9.5 and even in that version there is no handshake during role > reversal. In fact PG does not have concept of handshake and role reversal > unlike in Db2, oracle and sqlserver you can switchover from one to other by a > single command. > > Our DBAs use home grown script for switchover which does the following: > > 1 - first kill postmaster in the outgoing primary. Kill ? You mean "pg_ctl stop -m fast" right ? > 2 - promote the standby as the new primary > 3 - use timeline to resync former primary (of step 1) with the new primary > (step 2). Use timeline to resync ? Timeline is an internal mechanism in PostgreSQL, not a tool, so I don't get this step...You mean using pg_rewind ? So far, I stick to my procedure (given in another answer) which looks a lot more safer. > I hope a more elegant way exists as in other RDBMS. Me too. But it require a lot of work as a master is not able to "demote" as a standby without a restart. As far as I know, the standby code path is only accessible during startup. Note that you could switchover in one command as well using external tools like PAF [1][2]. But PAF comes with a lot more features than just switchover and rely on Pacemaker... [1] https://github.com/dalibo/PAF [2] http://www.dalibo.org/_media/2016-pgconfeu-paf.html.gz Cheers, -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
