SF5.1 VxDMP caches LUN size?

Can u clarify a bit more .... If I understand correctly, you had a lun size of xGB before, the same Lun has been resized to a bigger size ... lets say yGB & you are not able to see the new size correct ?

If this is correct, you should go with "vxdisk resize" option for veritas to understand the new lun size, this is called Dynamic Lun Expansion...

Check for Veritas Volume manager admin guide for details ..

What is the vxvm version you are using ?

G

Link for DLE in Linux

https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/vxvm_admin/ch03s16.htm

G

Hi Gaurav,

thanks for your fast comment! Ok, to be more presize:

1. I had an unused LUN #12 which was too small. The crappy flaky storage (Promise VTrak 610fD) does not support DLE, so I deleted the LUN, created a bigger one and mapped it out via the same LUN ID.

2. VxVM is SF 5.1 SP1 RP2 P2 (should be the most recent one for SLES11 in that series since I just patched that up)

3. Of course I tried that DLE stuff -- nothing happend because VxVM doesn't recognize the LUN is bigger

Currently I assume maybe it helps removing all references to this disk (DMP Nodes, info files) and do a 'vxdctl initdmp') but since this is a preproduction server I am a little bit anxious about destroying stuff that currently perfectly works.

Maybe I just change the LUN ID and disk name ....

Can you see real capacity using sg_readcap?

# sg_readcap /dev/sdX

You can try deleting SCSI device on Linux and rescanning.

Check for SCSI host adapter number:

# lsscsi
...
[0:1:2:0]    disk    LSILOGIC Logical Volume   3000  /dev/sda

Here the first number before colon is host adapter.

Now delete SCSI device for your disk(s) for this LUN

# echo 1 > /sys/block/sda/device/delete

Verify that disk is no more visible in lsscsi output and rescan

# echo '- - -' > /sys/class/scsi_host/host0/scan

Were hostN - is the number form the first step.

Notice that sdX names will change after that. So you will need to rescan in VxVM as well. It makes sense to try to remove disk from VxVM control first.

unfortunately yes, as you can see above in the fdisk output, so from the OS side everything is fine:

# sg_readcap /dev/sdt
Read Capacity results:
   Last logical block address=251658239 (0xeffffff), Number of blocks=251658240
   Logical block length=512 bytes
Hence:
   Device size: 128849018880 bytes, 122880.0 MiB, 128.85 GB
 

from the OS side everything is fine

sg_readcap goes directly to device using pass through. So it confirms that you have LUN with correct size mapped, but still OS may cache old size. In my experience such changes really require deleting old device and rescanning.

I know. As you can see above in my original post the OS is quite fine and uses 120GB, only DMP is sticking to those 80GB it had before. I can use the disk in the OS without any problems. Sorry :)