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Date: Mon, 25 Jul 2005 16:32:25 -0700
From: Danny Howard <dannyman@toldme.com>
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Subject: CARP Load-Balancing?  (Or, HTTP peer load balancing?)
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Hello,

I am looking at building a tiered web application (web layer, DB layer)
and am wondering about configuring automatic failover for the web layer.

If possible, I'd like to avoid having to implement a third firewall /
balancing tier, but if I must, I shall do that ...

I am looking at CARP.  The documentation seems soarse, and it sounds
like the "load balancing" option isn't much of an option.

On the other hand, I could set multiple vhids, one per web server, and
rig it up so that if one web server drops its interface, another will
answer for it.  Then "load balancing" is as simple as putting multiple
web server IPs in for the A record ...

(With CARP basically functioning as a "heartbeat" monitor ...)

Does that sound sensible?  I'm feeling a bit wary of this approach.

Any suggestions for handling failover of HTTP among peers?

Thanks,
-danny