[Mailman-Users] migrating hundreds of lists to another host

[Zhengquan Zhang]

On Thu, Jun 04, 2009 at 06:43:06PM +0100, Adam McGreggor wrote:
> On Wed, Jun 03, 2009 at 12:50:01PM -0500, Zhengquan Zhang wrote:
> > Hi mailman list,
> > 
> > Since our list server is getting old and dying, I plan to migrate list
> > service to another host.
> > 
> > mailman is working with a postfix setup. the migration will be temporary
> > and once I setup a new server for the list I will move the lists back.
> > 
> > My question is, how Can I minimize list downtime and allow for users to
> > use the lists without any feeling the service has been moved to another
> > host? for example, the hostname is different for the temporary host and
> > others? I am clueless asto how to do this.
> 
> So, ideally, you want to get something quick and dirty working for a
> few hours, whilst you commission and build/do final config of a new
> server?

Well, it is not a few hours, the old server still has other services
running, so I will gradually migrate all services seemlessly to the
temporary server and at the same time build a new server and get things
back to the new server.

> 
> Two (and an half) ideas spring to mind:
>     (a) rsync the mailman & mta configs over to $TEMPBOX, adjust
>         Mailman default configs, fix-up URIs/mail addresses,
>         set forwarding of Mailman addresses on $OLDMTA to $TEMPBOX,
>         fix-up $HTTPD to proxy out Mailman stuff (vaguely)
>     (b) Switch-off/disable (list)-mail on $OLDHOST, and rely on 
>         secondaries until $NEWHOST is ready... 
>     (c) Make your MTA just bounce back to listmembers, posting to your
>         list addresses (listmembers, sort, uniq), saying something
>         like "Down for maint, try again in a couple of hours/check the
>         status <http://status.example.org> pages".
> 
> As I gather, $NEWHOST will be a replacement (with the same 
> hostname, ip addy, services &c) to $OLDHOST.
> 
> There's a bit of effort (even scripted) in doing (a), and it'll
> need to be undone/reversed when you bring $NEWHOST up. I'm a lazy
> sysadmin, so would probably go down (b) route. I might shove something
> out for info, (c), but depends how pressed for time I was/how long the
> move/build would take.

So it seems harder than I expected to really have the list services
migrate to another host seamlessly.

I will do more searching of the mailman-user archives.

> 
> And I would have most of the new-machine built/config'd, so it would
> just be a case of downing, changing network settings, and bringing the
> new-machine up; should be <30mins; then however long to copy over
> Mailman's data/archives.

Thanks for your help, 

-- 
Zhengquan