Sometimes quotas will be enabled on a backup partition which is not recommended due to potential performance issues.
You can confirm if quotas are enabled by checking the /etc/fstab file:
[13:01:56 rs009 root@93566992 ~]cPs# grep quota /etc/fstab
UUID=08ec4d96-034e-4c3e-b199-9f3753de7171 / ext4 defaults,usrquota,grpquota 1 1
[13:02:04 rs009 root@93566992 ~]cPs#
To disable quotas you would need to remove the usrquota and grpquota entries in the fstab.
After these are removed the partition will need to be remounted or the server rebooted:
mount -o remount $MOUNTPOINT
There are additional steps when the filesystem is XFS: