EL5 hard drive dm-0 problem

funnyvoice · 06-02-2009, 02:05 PM

Hi

I've got a rather silly problem. It seems to me, that my disk/partitions are very messed up. I've got one sata drive and then another ide drive.

My sata works fine, gets picked up and everything, but my ide is picked up at boot time, and then assignd the drive dm-0. When I try to mount it, the device dm-0 does not exist.

Here is my partitions:
major minor #blocks name

3 0 78150744 hda
3 1 104391 hda1
3 2 78043770 hda2
253 0 75988992 dm-0
253 1 2031616 dm-1
8 0 156290904 sda
8 1 90751153 sda1
8 2 61440592 sda2
8 3 4096575 sda3
8 16 7823360 sdb
8 17 7819328 sdb1

Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
71G 27G 41G 40% /
/dev/hda1 99M 26M 69M 27% /boot
tmpfs 1006M 0 1006M 0% /dev/shm
/dev/sda2 57G 31G 24G 57% /home
/dev/sdb1 7.5G 6.9G 646M 92% /media/STORE N GO

Ignore sdb1, that is my flash drive. I'm trying to mount device dm-0/hda2. When I try to mount, it replies that its already mounter. So I gather its lvm right?

My system is scientific linux 5.2, or Red Hat EL5 clone if you will

ANy help would be nice!?

Ta

tommylovell · 06-02-2009, 09:49 PM

Yes, it is LVM. Use 'dmsetup ls' to display what logical device it is.

One my system, "dm-0" is "vgz00-lvz01" (full path is "/dev/mapper/vgz00-lvz01" or "/dev/vgz00/lvz01", a soft link to "/dev/mapper/vgz00-lvz01"). And my "/dev/mapper/vgz00-lvz01" LVM logical volume is mounted on "/".

You probably have something similar, hence the inability to mount it again.

Code:

[root@athlonz ~]# cat /proc/partitions 
major minor  #blocks  name

   8     0 1465137527 sda
   8     1     104391 sda1
   8     2   25005172 sda2
   8     3          1 sda3
   8     5 1440026406 sda5
   8    16 1465137527 sdb
   8    17     104391 sdb1
   8    18   25005172 sdb2
   8    19          1 sdb3
   8    21 1440026406 sdb5
   9     0   25005056 md0
 253     0   23920640 dm-0
 253     1    1048576 dm-1
   9     1 1440026304 md1
 253     2  562036736 dm-2
 253     3      32768 dm-3
 253     4  314572800 dm-4

[root@athlonz ~]# dmsetup ls
vgz01-hfsplus   (253, 3)
vgz00-lvz01     (253, 0)
vgz00-lvz00     (253, 1)
vgz01-maclv     (253, 4)
vgz01-lvz00     (253, 2)

[root@athlonz ~]# mount
/dev/mapper/vgz00-lvz01 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/mapper/vgz01-lvz00 on /bkup type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
/dev/sdb1 on /boot2 type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
nfsd on /proc/fs/nfsd type nfsd (rw)

tommylovell · 06-02-2009, 10:27 PM

btw, in case you're curious, the PV's in my other reply are software RAID. "/dev/md0" is RAID1 composed of two partitions, "/dev/sda2" and "/dev/sdb2"; "/dev/md1" is another RAID1 array composed of two partitions, "/dev/sda5" and "/dev/sdb5"

Code:

[root@athlonz proc]# cat /proc/mdstat
Personalities : [raid1] [raid6] [raid5] [raid4] 
md1 : active raid1 sda5[2] sdb5[1]
      1440026304 blocks [2/2] [UU]
      
md0 : active raid1 sdb2[1] sda2[0]
      25005056 blocks [2/2] [UU]
      
unused devices: <none>

[root@athlonz proc]# pvs
  PV         VG    Fmt  Attr PSize  PFree  
  /dev/md0   vgz00 lvm2 a-   23.84G  32.00M
  /dev/md1   vgz01 lvm2 a-    1.34T 537.28G

[root@athlonz proc]# vgs
  VG    #PV #LV #SN Attr   VSize  VFree  
  vgz00   1   2   0 wz--n- 23.84G  32.00M
  vgz01   1   3   0 wz--n-  1.34T 537.28G

[root@athlonz proc]# lvs
  LV      VG    Attr   LSize   Origin Snap%  Move Log Copy%  Convert
  lvz00   vgz00 -wi-ao   1.00G                                      
  lvz01   vgz00 -wi-ao  22.81G                                      
  hfsplus vgz01 -wi-a-  32.00M                                      
  lvz00   vgz01 -wi-ao 536.00G                                      
  maclv   vgz01 -wi-ao 300.00G