Karanbir Singh wrote:
Christopher Chan wrote:
No, mail spools/queues do not need replication. Stuff in the queue are
usually deleted in a second and such dynamic change is not worth
replicating. If you do put the queue on a distributed filesystem, in
most cases you cannot have more than one instance running save for
sendmail.
I think your statement here is flawed, in that if there is even a single
bit of the process you dont replicate - you've already lost the HA game.
I am sorry but I do not share that view for incoming mail. The latency
in getting the mail replicated probably is longer than it takes to do
the actually delivery to the mail store.
Besides, as John already pointed out, emails in the spools can hang
around for days. I believe most MTA's only discard completely after
7days of non delivery.
That default setting is no longer applicable today. Users will scream if
they find out that their mails have been sitting in the queue for a day.
For today's businesses, one day can make or break a deal and so email,
being a much faster form of communication than snail mail, has come to
be seen as the preferred choice. People start calling when they know
they are supposed to get an email in a minute or so when it does
materialize.
the OP is taking about DRBD in a primary-> secondary setup, in which
case, there wont be a clustered filesystem on the block device, and
there will only really be one instance of the real app running.
He is welcome to replicate the queue. His traffic levels will be so low
that it really does not affect things but if he is using qmail I hope
that the filesystem is completely identical on the secondary.
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
http://lists.centos.org/mailman/listinfo/centos
