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I was Trying to read the apache access log for my vps server and i have found something wired , it has almost 98% of the requests from same IP address of the vps here is an example of logs - - [02/Feb/2012:16:39:58 +0400] "GET /css/demo_table.css HTTP/1.1" 200 9933 "-" "Serf/0.7.2 mod_pagespeed/"

it counts 23943 form this ip , how to explain that ??

notes : i had mod pagespeed enabled

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up vote 4 down vote accepted

mod_pagespeed has an agent, Serf, which is fetching the non-optimised version of the page. So every request into your system with mod_pagespeed enabled looks like:

external client->mod_pagespeed/Serf proxy->real page.

I would expect every external request for a page mod_pagespeed hasn't optimised and cached to result in Serf request, which will comes from the server's own IP address.

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your answer seems to be good , but could you please provide the prove of it , thanks – tawfekov Feb 8 '12 at 10:39
Have a read through: which discusses the architecture and mentions Serf and explains the caching behaviour. – Rodger Feb 8 '12 at 18:04

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