Command to check mod_pagespeed is installed in server.
curl -D http://127.0.0.1
You will get below output.
Date: Fri, 07 Sep 2012 21:51:06 GMT
Server: Apache/2.2.3 (CentOS)
X-Mod-Pagespeed: 0.10.22.4-1633
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curl -D http://127.0.0.1
You will get below output.
Date: Fri, 07 Sep 2012 21:51:06 GMT
Server: Apache/2.2.3 (CentOS)
X-Mod-Pagespeed: 0.10.22.4-1633