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<DIV><FONT face=Arial size=2>We recently switched from serving directly from
Apache to using Varnish in front as a cache.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So we have:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> varnish -> apache -> mongrel
(rails)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>and in front of varnish we have a hardware
load-balancer (as a service of our hosting provider, softlayer)
which</FONT></DIV>
<DIV><FONT face=Arial size=2>balances traffic to 3 servers.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>In the past, as soon as we took down apache on one
of our servers, the load balancer would detect it and route</FONT></DIV>
<DIV><FONT face=Arial size=2>all traffic to the other servers.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>However, since we started running varnish, the load
balancer doesn't seem to detect that a server is down, and so</FONT></DIV>
<DIV><FONT face=Arial size=2>it keeps sending traffic even after varnish has
quit.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Has anybody run into any similar problems, or have
any ideas why we would see different behavior running Varnish</FONT></DIV>
<DIV><FONT face=Arial size=2>as opposed to simply Apache?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>--Scott Persinger</FONT></DIV>
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