Why the duplicate device file names are like "/dev/sddlmaa, /dev/sddlmab and /dev/sddlmac" in linux.

[senthil_kumar_1]

We have three LUNs in SUSE linux (SLES 9) coming fomr hitachi storage..

So that the device files are shown like "sda, sdb and sdc"...We are using this only...

Apart from this there are 3 more device files like "/dev/sddlmaa, /dev/sddlmab and /dev/sddlmac".


We can find this from fdisk.


Example:


# fdisk -l

Disk /dev/sda: 53.6 GB, 53687091200 bytes
255 heads, 63 sectors/track, 6527 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 1 132 1059389 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 1307 2611 10482412+ 83 Linux
/dev/sda3 2612 4569 15727635 83 Linux
/dev/sda4 4570 6527 15727635 83 Linux

Disk /dev/sdb: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 1 8355 67111506 83 Linux
/dev/sdb2 8356 9661 10490445 83 Linux
/dev/sdb3 9662 10967 10490445 83 Linux
/dev/sdb4 10968 13054 16763827+ 5 Extended
/dev/sdb5 10968 12184 9775521 83 Linux

Disk /dev/sdc: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdc1 1 7181 57681351 83 Linux
/dev/sdc2 7182 8878 13631152+ 83 Linux
/dev/sdc3 8879 12794 31455270 83 Linux


Disk /dev/sddlmaa: 53.6 GB, 53687091200 bytes
255 heads, 63 sectors/track, 6527 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sddlmaa1 1 132 1059389 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sddlmaa2 1307 2611 10482412+ 83 Linux
/dev/sddlmaa3 2612 4569 15727635 83 Linux
/dev/sddlmaa4 4570 6527 15727635 83 Linux

Disk /dev/sddlmab: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sddlmab1 1 8355 67111506 83 Linux
/dev/sddlmab2 8356 9661 10490445 83 Linux
/dev/sddlmab3 9662 10967 10490445 83 Linux
/dev/sddlmab4 10968 13054 16763827+ 5 Extended
/dev/sddlmab5 10968 12184 9775521 83 Linux

Disk /dev/sddlmac: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sddlmac1 1 7181 57681351 83 Linux
/dev/sddlmac2 7182 8878 13631152+ 83 Linux
/dev/sddlmac3 8879 12794 31455270 83 Linux

[Steven Schweda]

I know nothing, but a Google search for
/dev/sddlmaa
suggests that you might have HDLM software
installed.

http://hdsguides.com/uspv-vm/HDLM-ConceptsandPlanningGuide.html

> So that the device files are shown like
> "sda, sdb and sdc"...We are using this
> only...

Then perhaps you wasted the money you paid
for HDLM (if any).

[Alzhy]

You definitely have HDLM.

You should have just used native multipathing in Linux (device mapper multipath).

Please read through Hitachi's document so the HDS disks are excluded from Linux's device mapper multipath control and be aware or you could whack/user/reuse/initialize the wrong disk.

Please also be familiar with "blkid"