Paul Berger wrote: > I read a CentOS bugzilla http://bugs.centos.org/view.php?id=3853 that > indicated that the functionality may exist in the kernels yet, but > just the user space tools were missing. After doing some testing, the > persistent caching does not appear to be in the kernels, either that > or process outlined in the bugzilla entry and > http://people.redhat.com/steved/fscache/docs/HOWTO.txt are missing > something. Looks like that CentOS bug listing is not quite right - the FS-Cache code is still in the 5.[34] kernels (and the fscache.ko module is available), but the 'fsc' mount option in the nfs client module has been disabled - from the kernel changelog: * Sat Sep 13 2008 Don Zickus <dzickus at redhat.com> [2.6.18-115.el5] ... - [nfs] disable the fsc mount option (Steve Dickson ) [447474] > I also tried the Centos Plus kernel to see if it's be enabled in there > and the results appear to be the same. > > Apparently I need to use either Fedora 12 if I want to use this > feature now, use CentOS 5.2 and not update as waiting till CentOS 6 is > not really an option. I really hate using bleeding edge and not > updating and running with packages with know security vulnerabilities > (even on our internal networkd) seems like a poor idea. ::sigh:: Theoretically, you could rebuild a more recent CentOS 5.[34] kernel with the 'linux-2.6-nfs-disable-the-fsc-mount-option.patch' commented out in the spec file - but as I mentioned previously, the FS-Cache code that is in these kernels is now quite old (and buggy). If you really need to use FS-Cache now, then you need to use something like Fedora 12 or, as I have recently done, use CentOS 5 with a recent mainline kernel (2.6.32-rc8-git4 has up to date FS-Cache patches) and a more recent nfs-utils version - see: <http://www.redhat.com/archives/linux-cachefs/2009-October/msg00002.html> James Pearson