CentOS - Oct 2015 - mount: unknown filesystem type '(null)' error

Hey guys,

 I'm trying to mount a disk volume on aws under CentOS 7. And when I try I
get this result:

[root at repo:~] #mount /dev/xvdf1 /opt/repo
mount: /dev/xvdf1 is write-protected, mounting read-only
mount: unknown filesystem type '(null)'

The only thing I can see in dmesg that seems to relate is:


[ 2481.434610] EXT4-fs (xvdf1): VFS: Can't find ext4 filesystem
[ 2509.883144] EXT4-fs (xvdf1): VFS: Can't find ext4 filesystem


What can I do to get around this poblem?

Thanks,
Tim

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