[RESOLVED] XFS kernel module missing in CentOS 6

secant · Post by **secant** » 2011/07/16 20:28:08

I'd like to run CentOS 6 on my NAS, but I can't seem to find the xfs kernel module (package 'kmod-xfs') in any of the CentOS 6 repositories. It's available on CentOS 5.6, though. I need to be able to use xfs, since that is the filesystem I chose for the storage array, and I have already moved all my data to it. Is there a way for me to install the xfs kernel module in CentOS 6, or will I need to go back to my less-stable Fedora installation?

Thanks!

Post by **toracat** » 2011/07/16 20:42:16

xfs.ko is part of the kernel in CentOS-6. No need to install as an external kernel module.

secant · Post by **secant** » 2011/07/16 22:09:20

I have performed a minimal installation of CentOS 6, and it can't mount the existing xfs partition. I created a different xfs partition on a flash drive, and was unable to mount that either. The exact error message I get is:

[code]
mount: unknown filesystem type 'xfs'
[/code]

I am assuming this means that the kernel doesn't have xfs support.

Since I am unable to mount my existing xfs partition with the default kernel, I tried upgrading to the centosplus kernel, by enabling the CentOS Plus repository. This kernel also didn't recognize either xfs filesystem. Are there other packages that I need to install, or perhaps a different kernel I should be using instead of the default (or centosplus) one?

Right now, I'm running kernel 2.6.32-71.29.1.el6.centos.plus.i686, and I was previously running the more recent default kernel 2.6.32-71-29-1-el6.i686.

Thanks for your help.

Post by **toracat** » 2011/07/16 22:16:49

Both the distro kernel and centosplus kernel have the xfs module. Try (as root):

modprobe xfs

and check to see if the module has been loaded by:

lsmod | grep xfs

secant · Post by **secant** » 2011/07/16 22:38:34

modprobe fails with

[code]
FATAL: Module xfs not found.
[/code]

lsmod lists several loaded modules (including modules for ext2 and ext4), but the xfs module is unfortunately not among them. The only deviations from the normal, standard installation you are expecting were that I chose the "minimal" package set (so maybe I'm missing some crucial package), and that it was a netinstall. Other than that, I don't know why the kernel I have installed doesn't include xfs support.

Do you know anything else I can try?

EDIT:

Alan, that find returns no matches. xfs.ko has mysteriously vanished!

AlanBartlett · Post by **AlanBartlett** » 2011/07/16 22:38:50

And please also post the output returned by executing --

[code]
[b]find /lib/modules -name xfs.ko -type f[/b]
[/code]

Post by **TrevorH** » 2011/07/16 22:50:24

Looks like it's not in the ix86 version.

[code]
[root@eee ~]# modprobe xfs
FATAL: Module xfs not found.
[root@eee ~]# locate xfs.ko
[root@eee ~]# yum provides \*/xfs.ko
Loaded plugins: changelog, downloadonly, fastestmirror, protect-packages, refresh-packagekit,
: security, versionlock
Loading mirror speeds from cached hostfile
* base: mirrors.dedipower.com
* extras: mirrors.dedipower.com
* updates: mirrors.dedipower.com
base | 3.7 kB 00:00
extras | 951 B 00:00
updates | 3.5 kB 00:00
No Matches found
[root@eee ~]#
[/code]

secant · Post by **secant** » 2011/07/16 23:05:01

Well that's a shame... this machine isn't capable of running a 64-bit OS. Would anyone happen to know when xfs support will be included in the i386 kernel, or if it's even planned?

Post by **toracat** » 2011/07/17 00:35:38

That should have occurred to me -- xfs is available only for the x86_64 version of CentOS-6. Thanks, TrevorH, for noticing it.

It is unlikely that upstream will add xfs to the 32-bit OS because xfs tends to have some issues with 4k stacks on the 32-bit kernels.

AlanBartlett · Post by **AlanBartlett** » 2011/07/17 01:09:04

[quote]
Alan, that find returns no matches. xfs.ko has mysteriously vanished!
[/quote]
Of course, I [i]should[/i] have also asked you for your system's architecture . . .

It's all "water under the bridge" now that [b]Trevor[/b] has "put his finger on it".

CentOS