client keepalive on high trafic site

Poul-Henning Kamp phk at
Tue Sep 8 12:53:22 CEST 2009

In message <4AA63655.5020707 at>, =?UTF-8?B?VsOhY2xhdiBCw61sZWs=?= writes:

>Because i am not shure how to do that ...
>I cant test User-Agent in vcl_deliver because 'req.' object is not
>accesible there
>where shoud i put such a test?

Ahh, that gets trick if you are running a version before we enabled that.

How much IE6 traffic do you have ?

If it is not too much, you could simply pass it.

If it is too much for that, one dirty workaround is to define
yourself as a backend, and send all IE6 to pass with yourself
as backend, that way you get a cache-hit, but can use vcl_fetch
on the pass transaction to nuke the connection closed header.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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