Re: Missing timeline history file after execution of pg_upgrade

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Feb  4, 2015 at 09:23:56AM +0100, Alexey Klyukin wrote:
> On Tue, Feb 3, 2015 at 10:41 PM, Alexey Klyukin <alexk@xxxxxxxxxxxx> wrote:
> > The path to reproduce the problem is quite simple:
> >
> > - setup the master and the replica setup, and promote the replica,
> > creating a new timeline (timeline 2 by default)
> > - pg_upgrade the promoted replica. This would create a new cluster
> > with the same timeline, but without the history file.
> > - create the streaming-only replica. The streaming replication will
> > never start, since the timeline file is not there. The error messages
> > are:
> >
> > ERROR:  could not open file "pg_xlog/00000002.history": No such file
> > or directory
> > FATAL:  could not receive timeline history file from the primary
> > server: ERROR:  could not open file "pg_xlog/00000002.history": No
> > such file or directory
> >
> > Note that this problem does not occur for the streaming-only replica
> > of the newly created cluster (with a timeline 1), even when there is
> > no timeline history file in the original datadir.
> 
> 
> In our case I solved the problem by manually creating a 00000002.history file
> on master. It consists of the previous timeline (obviously 1), the location when
> the new timeline has been created (lost) and the text reason, which can be
> arbitrary. As for the location, I don't think it matters much, since
> we don't have
> branched timelines and not going to switch to timeline 1 again, I've
> put the value
> of the 'Prior checkpoint location' from pg_controldata on the replica,
> but I think
> I could just put all 0 with the same effect.
> 
> Nevertheless, the question is should pg_upgrade move the timeline history file
> from the old server to the new one, and, to be more specific, are
> there any cases when
> moving such file is not recommended?

Sorry I am just getting to this --- you are right it is a bug.  I was
unaware that pg_upgrade passed the timeline from the old cluster, but it
does so when setting the WAL starting address with pg_resetxlog -l,
which includes the timeline as the first eight hex digits.

I think there are two options:

1)  force pg_resetxlog -l to pass timeline 1
2)  create a WAL history file to match the old cluster's timeline (!= 1)

I don't think we want to be doing #2, so I have developed the attached
patch for #1, which I should backpatch to 9.4.  Do we store the timeline
in any user tables that might be transfered?  Anywhere else?

-- 
  Bruce Momjian  <bruce@xxxxxxxxxx>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + Everyone has their own god. +
diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c
new file mode 100644
index fbccc2e..cc81fa0
*** a/src/bin/pg_upgrade/pg_upgrade.c
--- b/src/bin/pg_upgrade/pg_upgrade.c
*************** copy_clog_xlog_xid(void)
*** 473,480 ****
  	/* now reset the wal archives in the new cluster */
  	prep_status("Resetting WAL archives");
  	exec_prog(UTILITY_LOG_FILE, NULL, true,
! 			  "\"%s/pg_resetxlog\" -l %s \"%s\"", new_cluster.bindir,
! 			  old_cluster.controldata.nextxlogfile,
  			  new_cluster.pgdata);
  	check_ok();
  }
--- 473,481 ----
  	/* now reset the wal archives in the new cluster */
  	prep_status("Resetting WAL archives");
  	exec_prog(UTILITY_LOG_FILE, NULL, true,
! 			  /* use timeline 1 to match controldata and no WAL history file */
! 			  "\"%s/pg_resetxlog\" -l 00000001%s \"%s\"", new_cluster.bindir,
! 			  old_cluster.controldata.nextxlogfile + 8,
  			  new_cluster.pgdata);
  	check_ok();
  }
-- 
Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-admin

[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux