Lähettäjä: Patrick von der Hagen Päiväys: Vastaanottaja: exim-users Aihe: Re: [exim] Delivering Mail and 2 different Locations
Am Montag, den 03.12.2007, 20:35 +1100 schrieb Ted Cooper: > Gaurav Pruthi wrote:
> > Hi,
> >
> > I m using exim with mysql. I want exim to deliver mail to 2 different
> > locations. How this can be done? My only concern is that in case 1st
> > location goes offline, i can switch to another location with minute changes
> > in mysql (changing the path only to deliver the mail). I have 2 SANs. One is
> > where the actual mail is being delivered. I want to keep a live backup of
> > 1st to 2nd with the same structure so that in case of any mishappening, the
> > downtime is equal to negligible.
>
> Use a duplicate pair of routers/transports with the same conditions and
> make the first one "unseen".
> The specific details would depend on you configuration so you're best to
> check out your config and read the manual around .. I'd like to point out that one would probably want to take care with
this approach to prevent non-delivery-warnings and -errors when one of
the recipient-severs is down. Otherwise users are likely to complain
about error-notifications when everything is working fine...
But I wouldn't really be me if I didn't point out that the concept, as
far as I can see it at the moment, seems to be flawed. The delivered
messages will be read (i.e. changed) after delivery, so it is not just
exim which has to support duplication for two locations, but every
actions by the users has to be duplicated too. Currently I see no
solution, perhaps cyrus+murder?
The easies way would probably be to run some replication on SAN-level.
If the SANs have different vendors or replication is to expensive, drbd
should work with SAN-blockdevices. Not sure wheter anybody actually
tryed to to that, though. ;-)
Question is, wheter "two locations" really mean two different geographic
locations. That would be a real challenge.
At least the exim-side is the smalles problem. But when the other
problems are solved, I expect that "global" solution to offer an
exim-solution more or less as a side-effect.