[root@server ~]# df -hT /var/lib/mysql_backup/
Filesystem    Type    Size  Used Avail Use% Mounted on
/dev/mapper/sys-mysql_backup
xfs 25G 19G 6.3G 76%Â /var/lib/mysql_backup
[root@server ~]# lvcreate -s -n bkp-snap -L1G /dev/sys/mysql_backup
Logical volume "bkp-snap" created
[root@server ~]# mount /dev/sys/bkp-snap /mnt/misc/
mount: wrong fs type, bad option, bad superblock on /dev/sys/bkp-snap,
missing codepage or other
In some cases useful info is found in syslog - try
dmesg | tail or so
[root@server ~]# dmesg | tail -1
XFS: Filesystem dm-9 has duplicate UUID - can't mount
[root@server ~]# mount -o nouuid /dev/sys/bkp-snap /mnt/misc/
[root@server ~]# dmesg | tail -3
XFS mounting filesystem dm-9
Starting XFS recovery on filesystem: dm-9 (logdev: internal)
Ending XFS recovery on filesystem: dm-9 (logdev: internal)
[root@server ~]# xfs_admin -U generate /dev/sys/bkp-snap
Clearing log and setting UUID
writing all SBs
new UUID = 1bdcf6e1-62fb-47f2-83e4-dc398bb7a1cd
[root@server ~]# dmesg | tail -2
XFS mounting filesystem dm-9
Ending clean XFS mount for filesystem: dm-9
Hello,
Can you explain the benefits of using XFS in your situation ? I’m just curious, there are so many filesystems around that it is sometimes complex to pick a choice !
Thanks in advance
Stéphane
Hi Stephane,
XFS was a default choice for many years in the company when I arrived here. Some of the reasons are very good handling of big files (important for DB servers for example), fast recovery and possibility of online resize (ext3 was not able to do this at the time).
But there are some downsides as well. For example XFS is very prone to fragmentation so from time time defragmentation is necessary (although this can be done online). Also it is not a “standard” filesystem, so many backup solutions do not work with XFS (although they support reiserfs, blah!). We are having a big problem finding good online system backup solution for our servers. I would be grateful for recommendations! :-)