README-CentOS6

Vadim T (Percona) wrote an initial guide on getting flashcache building on CentOS, which was extremely helpful.

Based on that, I've modified the Makefiles to make building on CentOS as easy as possible. Here's the steps you'll
need to follow to build on CentOS:

 - Make sure you have the CentOS EPEL repo. (http://fedoraproject.org/wiki/EPEL)
 - Make sure you have the CentOS source repo. (http://mirror.centos.org/centos/$releasever/updates/SRPMS/)
 - Install prerequisite build packages:
   yum install dkms gcc make yum-utils kernel-devel
 - CentOS kernel-headers/devel packages don't include internal headers, we've got to configure the full source:
   yumdownloader --source kernel-`uname -r`
   sudo rpm -ivh kernel-`uname -r`.src.rpm
 - For CentOS6.x boot support:
   yum localinstall utils/dracut-flashcache-0.3-1.el6.noarch.rpm
   follow the instructions in doc/dracut-flashcache.txt later on if you want flashcache to accelerate your root device or lvm volumes
   skip the "Boot from Flashcache" part in README-DKMS

Now the updated Makefiles should work correctly.

Graeme Humphries <graeme@sudo.ca>