Re: anti-spam software

[Paul Russell <prussell () ND EDU>]

On 7/28/2008 4:20 PM, Bob Bayn wrote:
> In defense of the Barracuda folks, I will say that their tech
> support were very responsive and helpful with our occasional
> earlier problems, many of which were the result of our novice
> level of understanding how to manage them.  We were quite
> satisfied until the thrashing started.  I don't know what was
> the cause of our problem or how it might have been possible to
> resolve it without switching to a different system.

Unless Barracuda has made radical changes in the underlying architecture
of their product, it appears to me that clustered Barracuda Spam Firewall
(BSF) servers are doomed to thrash.  As the number of servers and/or the
number of messages being quarantined increases, the thrashing is likely to
become worse.  We encountered similar performance problems with a clustered
pair of BSF model 600 servers.  At the time (~3 years ago), we were told
that every message in quarantine must be replicated to every server in the
cluster, so that a user will be able to access all his/her messages,
regardless of which server accepted the user's login.  Barracuda could
have avoided this problem by creating a single copy of each user's mailbox,
and routing  inbound messages and user logins to the server where the
user's mailbox resides.  That is the approach used by vendors of some
other anti-spam products.

Barracuda attempted to address our performance problems by swapping the
pair of 600's for a single 800, which was supposed to have built-in
redundancy and more capacity than a pair of 600's.  We continued to
experience a variety of problems with the Barracuda product.  Some
problems were fixed and never re-appeared; some problems were fixed
but re-appeared later; some problems were never fixed.  We stuck with
Barracuda for two years, then replaced the BSF 800 with a pair of
Sentrion MG "appliances" from Sendmail, Inc.

--
Paul Russell, Senior Systems Administrator
OIT Messaging Services Team
University of Notre Dame
prussell () nd edu