Mark Stosberg <[EMAIL PROTECTED]> writes:
> I was just comparing these two checklists for how to upgrade PostgreSQL
> with Slony:
>
> Official docs:
> http://main.slony.info/documentation/versionupgrade.html
>
> Jan Wieck's list:
> http://gborg.postgresql.org/pipermail/slony1-general/2007-January/005631.html
>
> The official docs suggest a full resubscribe is not required, but Jan
> recommends it.
>
> Do both routes work, or does the "full resubscribe" process in Jan's
> process add some additional value?
>
> I'll volunteer to help update the official docs if the result is that
> they are just out of date.

I have been involved with doing several PostgreSQL upgrades this month
using Slony-I; I don't think there are any enormous differences
between the approach that Jan described and what I described in the
documentation.

I'm not sure what you mean by "not requiring a full resubscribe"; when
you create a new node, that will certainly involve the "full"
subscription process, complete with copying all the data from all
replicated tables.

I used a process a *bit* different from what is described in either
place, because our environment was shaped a bit different:

- We had 4 nodes; 1 master, and 3 subscribers.

- Over a period of several days, I installed the new PG version on
  each of the subscriber nodes, and added a Slony-I replica on that new
  DB.  The DB was on the same host, so lived on a different port #.

- Once the new DB on the new PG version was up to date, I'd see about
  arranging an outage to drop out the old DB, and switch the new DB over
  to the preferred port number.

- Thus, last Friday, I had 3 hosts updated to PG 8.1, and only the
  'master' still running 7.4.

- We then had an outage that involved doing a MOVE SET to shift the
   master role to one of the PG 8.1 instances.

- I then installed PG 8.1 and set up a replica on the former "master"
  node.

- Next week, I'll drop the one 7.4 DB that's still running...

In view that people will have differing needs and clusters of
different shapes, I'm not sure it's of much value to describe how to
handle an upgrade in vastly more detail than is provided.  If you
think there's something missing, I'll listen...
-- 
(reverse (concatenate 'string "ofni.sailifa.ac" "@" "enworbbc"))
<http://dba2.int.libertyrms.com/>
Christopher Browne
(416) 673-4124 (land)
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