Something fishy

[Anders Berg]

Hi,

I have been noticing a weird behavior the last couple of days (I first
noticed this about a week ago). I have been hoping to find the error, but
it has been so random.

When I sometimes start up IE I get an old frontpage of VG Nett.

With old I mean the last frontpage I had up in my IE. If that was 1 day
ago, I get a 1 day old frontpage.
I am not sure it's Varnish that does this, but I can't see any obvious
errors or changes on any of the Squid's either. Today I got an email from
work that I am not the only one noticing this.
I find the whole thing weird, and I can't see no other reason than my IE
sends a IMS request and gets an answer that nothing is changed, or
something to that effect.

A quick study of HEAD's I have done shows only small differences from
Squid and Varnish:

(andersb) fw:andersb $ HEAD http://www.vg.no
200 OK
Cache-Control: max-age=900
Connection: close
Date: Thu, 10 Aug 2006 18:38:23 GMT
Accept-Ranges: bytes
Age: 43
ETag: W/"2b400e-28af1-44db7d1e"
Server: Apache/1.3.27 (Unix)
Content-Length: 166641
Content-Type: text/html; charset=iso-8859-1
Expires: Thu, 10 Aug 2006 18:53:23 GMT
Last-Modified: Thu, 10 Aug 2006 18:38:22 GMT
Client-Date: Thu, 10 Aug 2006 18:39:06 GMT
Client-Peer: 193.69.165.21:80
Client-Response-Num: 1
X-Cache: HIT from www.vg.no
X-Cache: HIT from www.vg.no

(andersb) fw:andersb $ HEAD http://www.vg.no
200 OK
Connection: close
Date: Thu, 10 Aug 2006 18:37:27 GMT
Via: 1.1 varnish
Age: 100
ETag: "2b400e-288d5-44db7c55"
Server: Apache/1.3.27 (Unix)
Content-Length: 166101
Content-Type: text/html; charset=iso-8859-1
Expires: Thu, 10 Aug 2006 18:52:27 GMT
Last-Modified: Thu, 10 Aug 2006 18:35:01 GMT
Client-Date: Thu, 10 Aug 2006 18:39:07 GMT
Client-Peer: 193.69.165.21:80
Client-Response-Num: 1
X-Varnish: 2002714009 2002603403

The only differences I see are these (except that the doc's are somewhat
different because of different timeouts):

Cache-Control: max-age=900 on Squid, no header like this on Varnish.

The next one is weird:

ETag: W/"2b400e-28af1-44db7d1e" on Squid
ETag: "2b400e-288d5-44db7c55" on Varnish.

Every ETag from Squid has a W/ before the tag. This is new to me, and I
don't know the implications. It's obviously consistent across all Squid's.

Accept-Ranges: bytes on Squid but none on Varnish, but that's not whats
causing this.

Anyone care to guess?

Anders Berg