Обсуждение: Slony for upgrades
Seems we didn't have any mention of Slony for upgrades in the migration section, so I added it: <para> It is also possible to use <productname>Slony</> to create a slave server with the updated version of <productname>PostgreSQL</>. The slave can be on the same computer or a different computer. Once it has synced up with the master server (running the older version of <productname>PostgreSQL</>), you can switch masters and make the slave the master and shut down the older database instance. Such a switch-over results in only several minutes of downtime for an upgrade. </para> -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://postgres.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +
On Mon, 15 Oct 2007, Bruce Momjian wrote: > Seems we didn't have any mention of Slony for upgrades in the migration > section, so I added it: > > <para> > It is also possible to use <productname>Slony</> to create a slave > server with the updated version of <productname>PostgreSQL</>. The > slave can be on the same computer or a different computer. Once it > has synced up with the master server (running the older version of > <productname>PostgreSQL</>), you can switch masters and make the slave > the master and shut down the older database instance. Such a > switch-over results in only several minutes of downtime for an upgrade. > </para> Bruce, do you think we should say several minutes of downtime? It's been my experience that the downtime is usually measurable in seconds. I don't think I've ever had a switchover take more than 1 minute. Excellent catch and good work by the way! -- Jeff Frost, Owner <jeff@frostconsultingllc.com> Frost Consulting, LLC http://www.frostconsultingllc.com/ Phone: 650-780-7908 FAX: 650-649-1954
Jeff Frost wrote: > On Mon, 15 Oct 2007, Bruce Momjian wrote: > > > Seems we didn't have any mention of Slony for upgrades in the migration > > section, so I added it: > > > > <para> > > It is also possible to use <productname>Slony</> to create a slave > > server with the updated version of <productname>PostgreSQL</>. The > > slave can be on the same computer or a different computer. Once it > > has synced up with the master server (running the older version of > > <productname>PostgreSQL</>), you can switch masters and make the slave > > the master and shut down the older database instance. Such a > > switch-over results in only several minutes of downtime for an upgrade. > > </para> > > Bruce, do you think we should say several minutes of downtime? It's been my > experience that the downtime is usually measurable in seconds. I don't think > I've ever had a switchover take more than 1 minute. > > Excellent catch and good work by the way! Thanks, changed to seconds. I thought someone told me <5 minutes a while ago but I might have been mistaken. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://postgres.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +
On Tuesday 16 October 2007 01:38, Bruce Momjian wrote:
> Jeff Frost wrote:
> > On Mon, 15 Oct 2007, Bruce Momjian wrote:
> > > Seems we didn't have any mention of Slony for upgrades in the migration
> > > section, so I added it:
> > >
> > > <para>
> > > It is also possible to use <productname>Slony</> to create a slave
> > > server with the updated version of <productname>PostgreSQL</>. The
> > > slave can be on the same computer or a different computer. Once it
> > > has synced up with the master server (running the older version of
> > > <productname>PostgreSQL</>), you can switch masters and make the
> > > slave the master and shut down the older database instance. Such a
> > > switch-over results in only several minutes of downtime for an upgrade.
> > > </para>
> >
> > Bruce, do you think we should say several minutes of downtime? It's been
> > my experience that the downtime is usually measurable in seconds. I
> > don't think I've ever had a switchover take more than 1 minute.
> >
> > Excellent catch and good work by the way!
>
> Thanks, changed to seconds. I thought someone told me <5 minutes a
> while ago but I might have been mistaken.
I might question the strict reference to Slony here. AIUI you could do the
same thing with Bucardo and a couple of other replication solutions as well.
--
Robert Treat
Build A Brighter LAMP :: Linux Apache {middleware} PostgreSQL
Robert Treat wrote: > On Tuesday 16 October 2007 01:38, Bruce Momjian wrote: > > Jeff Frost wrote: > > > On Mon, 15 Oct 2007, Bruce Momjian wrote: > > > > Seems we didn't have any mention of Slony for upgrades in the migration > > > > section, so I added it: > > > > > > > > <para> > > > > It is also possible to use <productname>Slony</> to create a slave > > > > server with the updated version of <productname>PostgreSQL</>. The > > > > slave can be on the same computer or a different computer. Once it > > > > has synced up with the master server (running the older version of > > > > <productname>PostgreSQL</>), you can switch masters and make the > > > > slave the master and shut down the older database instance. Such a > > > > switch-over results in only several minutes of downtime for an upgrade. > > > > </para> > > > > > > Bruce, do you think we should say several minutes of downtime? It's been > > > my experience that the downtime is usually measurable in seconds. I > > > don't think I've ever had a switchover take more than 1 minute. > > > > > > Excellent catch and good work by the way! > > > > Thanks, changed to seconds. I thought someone told me <5 minutes a > > while ago but I might have been mistaken. > > I might question the strict reference to Slony here. AIUI you could do the > same thing with Bucardo and a couple of other replication solutions as well. OK, I now say "like Slony": It is also possible to use replication like <productname>Slony</> to create a slave server with the updated version of <productname>PostgreSQL</>. The slave can be on the same computer or a different computer. Once it has synced up with the master server (running the older version of <productname>PostgreSQL</>), you can switch masters and make the slave the master and shut down the older database instance. Such a switch-over results in only several seconds of downtime for an upgrade. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://postgres.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +