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>>> .el5 smells like Red Hat, Red Hat doesn't do XFS. At least in
>>> nothing that is currently released AFAIR.
>> 5.4 has XFS
> I googled 5.4 and found a CERT that mentions 2.6.18-164. So i
> guess minimum kernel for 5.4 is way more recent than -128.
I think that while the 'xfs.ko' module is part of the base kernels
available standard with EL 5.4, there is an XFS (including 'xfsprogs'
and support) "layered product" from RedHat (that is an optional
extra license) which has become available starting from EL 5.4.
Apparently RH have finally realized that many of their enterprise
customers have large XFS based storage systems and these are not
going to be moved to 'ext4' any time soon (also because EL6 is not
going to appear for a while yet).
That's I think way EricS replied to consult the distribution
Alternatively there are the XFS RPMs from ElRepo or CentOSPlus or
SL5; since EL releases are supposed (mostly indeed in my experience)
to be binary-compatible within major releases, they work well across
all EL5 clones.