Re: Re: Slave enters in recovery and promotes when WAL stream with master is cut + delay master/slave

On 2013-01-18 03:05:47 +0900, Fujii Masao wrote:
> On Fri, Jan 18, 2013 at 2:35 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> > On 2013-01-17 13:47:41 +0900, Michael Paquier wrote:
> >> Slave does not try anymore to reconnect to master with messages of the type:
> >> FATAL:  could not connect to the primary server
> >>
> >> I also noticed that there is some delay until modifications on master are
> >> visible on slave.
> >
> >> I think that bug has been introduced by commit 7fcbf6a.
> >> Before splitting xlog reading as a separate facility things worked
> >> correctly.
> >> There are also no delay problems before this commit.
> >
> > Heikki committed a fix for at least the promotion issue, I didn't notice
> > any problem with an increased delay, could you check again if you still
> > see it?
> 
> I encountered the problem that the timeline switch is not performed expectedly.
> I set up one master, one standby and one cascade standby. All the servers
> share the archive directory. restore_command is specified in the recovery.conf
> in those two standbys.
> 
> I shut down the master, and then promoted the standby. In this case, the
> cascade standby should switch to new timeline and replication should be
> successfully restarted. But the timeline was never changed, and the following
> log messages were kept outputting.
> 
> sby2 LOG:  restarted WAL streaming at 0/3000000 on timeline 1
> sby2 LOG:  replication terminated by primary server
> sby2 DETAIL:  End of WAL reached on timeline 1
> sby2 LOG:  restarted WAL streaming at 0/3000000 on timeline 1
> sby2 LOG:  replication terminated by primary server
> sby2 DETAIL:  End of WAL reached on timeline 1
> sby2 LOG:  restarted WAL streaming at 0/3000000 on timeline 1
> sby2 LOG:  replication terminated by primary server
> sby2 DETAIL:  End of WAL reached on timeline 1
> ....

That's after the commit or before? Because in passing I think I
noticed/fixed a bug that could cause exactly that problem...

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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