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

[Adam McGreggor]

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?

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.

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.

-- 
``What is a committee?  A group of the unwilling,
  picked from the unfit, to do the unnecessary.''  (Richard Harkness)