problem in mounting an nfs export on a USB disk

[Tapas Mishra]

I have a USB disk which has 2 partitions.I exported one of them (on NFS)
and now I am trying to mount it at client machine.
Each time it gets error

mount -t nfs 192.168.1.19:/media/vol2 /mnt/nfs/
mount.nfs: access denied by server while mounting 192.168.1.19:/media/vol2

Here is the /etc/exports file entry

showmount -e on nfs server gives
Export list for tapas:
/media/vol2 */24

On the client machine nfs-client package is installed.
What more I need to check?
Is it logged some where?

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