Re: Installing multiple instances of Postgred on one FreeBSD server

Pretty informative Jim, thanx.

Do you remember which version, when, by who, were these shortcomings (different user, different port) resolved?
At the time it seemed like a very hard thing to implement in the current status of jails.
So, to rephrase, did it take a major jail re-write to achieve the above? or was it more on the hack-side?

On Ðåì 02 ÌáÀ 2013 08:58:49 Jim Mercer wrote:
> On Thu, May 02, 2013 at 10:10:51AM +0300, Achilleas Mantzios wrote:
> > Hi, i was just lurking around,
> > being previously interested in running pgsql in jail environment (must have been some years back)
> > i noticed that jails had issues with running many instances of postmaster listening on the same port
> > and with the same user (say e.g. postgres). So basically having cloned jails running pgsql was not
> > out of the box possible without tweaking either user or port.
> > Being many years out of freebsd admin, has this been remedied by now?
>
> yeah, those issues are no longer
>
> the key thing is to have things running on the base machine set to listen
> on a specific IP, rather than all interfaces, as many applications do by
> default.
>
> so, for instance, for ssh on the base system, you would do:
>
> sshd_enable="YES"
> sshd_flags="-o ListenAddress=120.121.122.123"
>
> this will prevent it from listening for ssh on the ip you intend to use for
> the jail.
>
> and in the jail, you can leave it listen on all interfaces, since, in the
> jail, it only has its own interface.
>
> in the case of pgsql, the best way to do it is to not have pgsql installed
> on the base server, and only run it in a jail (or a couple jails, if you are
> looking to smooth the upgrade from one to the next).
>
> if you want to run pgsql on the base server, then set:
> listen_addresses = '120.121.122.123'
> in postgresql.conf, and there will be no conflict of listeners.
>
> it issue of users/uids is moot, since the jail is independent of the main system.
>
> assuming you configure the base system to listen only on its own IP, installing
> on the jail, is no different than installing on a normal system.
>
> --jim
>
> >
> > On ?????? 01 ?????? 2013 16:24:01 Jim Mercer wrote:
> > > On Wed, May 01, 2013 at 02:21:44PM -0600, Benjamin Krajmalnik wrote:
> > > > So essentially we would have to run jails on this - does that affect
> > > > performance?
> > >
> > > i would say minimal impact.
> > >
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: Jim Mercer [mailto:jim(at)reptiles(dot)org]
> > > > Sent: Wednesday, May 01, 2013 2:20 PM
> > > > To: Benjamin Krajmalnik
> > > > Cc: pgsql-admin(at)postgresql(dot)org
> > > > Subject: Re: [ADMIN] Installing multiple instances of Postgred on one
> > > > FreeBSD server
> > > >
> > > > On Wed, May 01, 2013 at 01:58:21PM -0600, Benjamin Krajmalnik wrote:
> > > > > I would like to install PG 9.2 on the same server and use Slony to
> > > > > replicate the databases, and once everything is up take the 9.0
> > > > > cluster down.
> > > >
> > > > allocate a new ip to the server.
> > > > reconfigure/restart 9.0 to listen on the main IP (not "all" as default)
> > > >
> > > > use ezjail to create a freebsd jail on thenew IP
> > > >
> > > > install 9.2 in the jail
> > > >
> > > > treat it them as two servers.
> > > >
> > > > point clients at new ip.
> > > >
> > > > once migrated, delete all 9.0 from the main server.
> > > >
> > > > if you need to upgrade again, add another jail.
> > > >
> > > > stop and delete the old jail whe the next upgrade is complete.
> > > >
> > > > repeat as often as you want to upgrade.
> > > >
> > > > i'm pretty sure this can be adapted to linux, but i forget what their
> > > > jail equivilent is.
> > > >
> > > > the overhead is minimal
> > > >
> > > >
> > > >
> > >
> > >
> > -
> > Achilleas Mantzios
> > IT DEV
> > IT DEPT
>
>
-
Achilleas Mantzios
IT DEV
IT DEPT
Dynacom Tankers Mgmt