IBM DS3400 expand Logical Drive (LUN)

I have always liked IBM DS series management suite. I have claimed once that your first storage (and with it – your way of thinking about storage abstraction, I assume) is your favorite storage. I have been using the Storage Manager 9 for years now, even before it was 9 (I think that it was 7 then), and way before it has become 10-something version.

SM9 is the tool to manage the DS4xxx storage series (previously fastT series, if you can remember…), however, their “smaller” brothers, the DS3xxx series have arrived with something else claimed to be “Storage Manager” as well. It has began as SM2, and I was sure surprised to see it under the name “Storage Manager 10” today.

It seems as if someone wanted to make life easy, so everything is hidden behind some messy-looking dashboard. Finding the so-well-known abstraction logic is almost impossible for me, no matter how many times I will use this disaster of a product. Can’t complain about the storage devices – they are rather good, and although IBM has recently had some firmware issues and stability issues with some of its storage products – I can’t say I hate this device. Storage Manager 2 (or 10, today), however, is something I prefer to avoid.

After all this ranting and crying, I can share this piece of technical information. Storage Manager 10 (2, whatever) does not allow for Logical Drive to be expanded. You can expand the Raid Array – no problem. Just add some more disks to it, however, the free space created in that specific array will not be available for your reallocation pleasure – you cannot expand any of your existing Logical Drives with it.

Google has pointed me to that specific post which enlightened me with a new understanding of the DS series – the SM10, while being nothing more than a limited GUI for the storage-handicap IT persons, does not completely cancel the storage device’s abilities. The device can expand LUNs, so SM10 can allow it, secretly.

You need to know what you’re doing. I will copy/paste the contents of that blog entry for future use:

Expanding LUNs on a DS3000 series disk system:

First make sure you have enough space in your array. Next go to the script editor in the Storage Manager gui. Choose script editor. Type in a command like this:

set logicalDrive [“FINKOPAS01-BOOT”] addCapacity=50GB;

This would add 50GB’s to the disk “FINKOPAS01-BOOT”.

Now choose run command from the menu. After the disk system has expanded your LUN you should see the extra capacity in the disk management console window.

*NOTE*: This information was originally found here: http://www.systemx.co.nz/xcelerator/?q=node/99

The target link is dead there, unfortunately, however, the “secret” information is available for all.

Do not forget the semi-comma at the end of the line. It won’t work otherwise. IBM… 🙂

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33 Responses to “IBM DS3400 expand Logical Drive (LUN)”

  1. Rich Says:

    I agree.

    This is a terrible design. Not only can you not add your free space to an existing lun as you can on the 4300 and 4500 series but you have no way of monitoring how far along your lun creation is progressing.

    This new interface is total cumbersome and extremely crippled.

  2. ez-aton Says:

    Yes. It sux.
    I don’t really get this whole “dashboard which shows you everything” trend. I prefer the old way of solid logic and understandable structure.
    Probably shouldn’t be GUI designer, right?

  3. Apricot Says:

    Totally agree.

    DS4300 Was my first SAN experience and I found the original Storage Manager logical and simple, I thought actually helped a new comer understand the process.

    It only has 2 tabs, 1 for your array and logical drives and 1 for your hosts and the logical drives you have assigned to them. That’s it! That’s all you need, why make it so messy with all the new tabs and screens and wizards.

    I think it was aimed at the less techincal but I really don’t think it helps. And not being able to grow a logical drive! How basic and crucial is that!

    Phew, I feel better now.

  4. ez-aton Says:

    I could have not said it better. The old Storage Manger was an excellent tool, with simple logic and defined flow. Other tools nowadays (other vendors) are far inferior to it, and still – the have replaced it to SM2 with its terrible wizard interface.
    IBM are IBM, you know. Let them do whatever they deem right, and try to live around it 🙂

  5. mie Says:

    Agreed with the rest. The GUI sux big time. I managed to expand the LUN using the command but actual syntax should be something like this

    set logicalDrive [“FINKOPAS01-BOOT”] addCapacity=50 GB ;

    You need to put a space after the value & then specify the unit either bytes/MB/GB/. Default unit, if you’re not specifying the unit, should be in bytes.

    If you don’t put a space & only specify like 50GB, you’ll be getting syntax error

  6. mie Says:

    In regards to the statement “the free space created in that specific array will not be available for your reallocation pleasure – you cannot expand any of your existing Logical Drives with it.”

    You can re-allocate the free space via this command with some performance degradation. Again, launch the script editor & execute this command,

    Start Array[N] Defragment ;

    Replace N with your array number. Till then!!!

  7. Lundbye Says:

    DS3000 and DS4000 are two different storage systems from two different manufactures. You can not use the DS4000 storage manager on a DS3000 and visa versa.

  8. ez-aton Says:

    Of course, and sadly, this is true.
    It’s pity they did not develop some common API for their storage subsystems. I would have been happier if I could use the SM9 with DS4xxx, DS3xxx and even the 3 digit series, like DS300 and DS400. Would be nice, even if unreal 🙂

  9. PHiney Says:

    Just upgraded to SM 10.60. It now has “Show Logical Drive Action Progress”. no equiv ‘show array progress’ command tho for the ‘
    sudo /opt/IBM_DS/client/SMcli xxx-da02a xxx-da02b -c “set array [2] addDrives=(1,6 1,7);” -p xxxxx’ command.

    p

  10. PHiney Says:

    I’d like to add to what i just said ‘sudo /opt/IBM_DS/client/SMcli xxx-da02a xxx-da02b -c “show logicalDrive [“MAIN”] actionProgress;” -p xxxxxxxx’ does indeed report the progress of the array operation. I have two logical drives on this array, MAIN and VMWARE. MAIN is reporting 24% at the moment and VMWARE is reporting ‘No action in progress’. So on a test case of one instance, this must mean that when MAIN is finished, VMWARE will start and when it gets to 100%, the operation will be finished. Pity is discovered the add multiple drives to the array command (mentioned above) after starting this operation (did it thru the gui so i’m only adding one drive).

    PH

  11. PHiney Says:

    Bash script time :

    ####################################################
    #!/bin/bash

    DRIVE=$1
    PASSWD=xxxxxx
    DA=xxx-da02

    if [ -z “$DRIVE” ];then
    echo “$0 ”
    exit
    fi

    LINE=`/opt/IBM_DS/client/SMcli “$DA”a “$DA”b -c “show logicalDrive [“$DRIVE”] actionProgress;” -p $PASSWD | grep -i ‘No action in progress’`

    while [ -z “$LINE” ];do
    sleep 1800
    LINE=`/opt/IBM_DS/client/SMcli “$DA”a “$DA”b -c “show logicalDrive [“$DRIVE”] actionProgress;” -p $PASSWD | grep -i ‘No action in progress’`
    done
    if [ “$LINE” = “No action in progress” ];then
    /opt/IBM_DS/client/SMcli “$DA”a “$DA”b -c “show logicalDrive [“$DRIVE”] actionProgress;” -p $PASSWD | mail -s “$DRIVE complete” [email protected]
    fi
    ####################################################

    I’ve hard coded the Disk Array name but that could be handed in as a variable too.
    I also ran the following in /opt/IBM_DS directory so as to stop needing to sudo
    chown -R :users *
    chmod -R g+rw *
    chmod -R g+x client/SMcli*

  12. Jeffrey Says:

    Can the drive be usable after i run the add capacity command or do i have to wait until the whole operation is over?
    Urgent respone needed.
    Thanks

  13. ez-aton Says:

    The drive is usable, yes.
    However, somewhat slow. Usable, still.

  14. Andy E. Says:

    Windows based question…
    Does this command automatically increase the size of the drive presented in Windows Explorer?

    Cheers!

  15. ez-aton Says:

    No, as far as I know. This command will increase the physical disk size, as you would be able to see through the ‘Disk Manager’. You might be required to rescan the disks (right-click on the ‘Disk Manager’ icon and select ‘rescan’ and then ‘refresh’), but still – the partition (with the drive letter) would have to grow manually. You could perform this task using ‘diskpart.exe’ command. Search about it on the net. You will find helpful info there.

  16. Andy E. Says:

    many thanks ez-aton – worked perfectly!

  17. Glen Says:

    In case anyone was wondering, you can check the progress of the LUN expansion using script editor which will return the percentage complete of the operation

    show logicalDrive [“logicalDriveName”] actionProgress;

  18. How to extend a volume on an IBM DS3400 « On the third side Says:

    […] today, I found another blog post, telling more or less the same as this […]

  19. dammy Says:

    Hi,
    Thanks for the helpful post. In my case i extended the wrong volume ad wuld like to shrink the disk size so that the capacity can be added to the intended volume.

    Any help please? Cheers.

  20. ez-aton Says:

    That I do not know if possible…
    Sorry.

  21. Vittorio Says:

    Thank you guys this was very helpful!

  22. Tyler Says:

    After I ran the script:
    set logicalDrive [“MyLUN”] addCapacity=10 GB;
    to add extra capacity, the LUN status showed “Increase Capacity in Progress” while some other LUNs showed “Logical Drive Movement for Capacity Increase in Progress”.
    Is this normal behavior? I still have 200G of free capacity in the array. If it is taking free storage, why is it not taken from the free capacity?

  23. ez-aton Says:

    I think it tries to maintain a un-fragmented layout there, and when you add free space to a specific LUN, you enforce it to move other LUN data (push them onwards) to free that amount of space. This is only a guess, of course, but still…

  24. venthought Says:

    Hi, thank you for the thread. Just a question. Is there a firmware version requirement in order for me to execute the addCapacity script? my current controller fw is 06.70.69.00. As long as you have the SM ver10, I can execute this script already? Thanks for your advise in advance.

  25. ez-aton Says:

    I don’t know, however, I think it is possible with any firmware. Not sure about it, though.

  26. Redix Says:

    I’ve followed the procedure above and I’ve successfully expand my LUN. However in my windows host I didn’t see my LUN expand. Does any one have any advice?

  27. ez-aton Says:

    The OS is required to perform ‘scan’ command on the SCSI/FC bus for changed devices. In Windows, you should be able to scan for changes via the disk management. If you get no results, it might have to do with the FC drivers used by Windows, firmware updates, or the storage firmware version. An unknown, to be exact. A reboot of the host should refresh the LUN, in case other, online operations, fail. Harsh, but sometimes, that’s the only option.

    Ez

  28. Redix Says:

    Thank you very much for your reply Ez, I discovered that my host doesn’t recognize more than 2 TB capacity of LUN. So I need to convert my LUN from MBR to GPT.

    This will be a long process to go. 🙁

  29. ez-aton Says:

    Yep. I am sorry for that. I wonder if there is no quick method, with data preservation, of migrating to GPT… It’s not supposed to change the data contents, just the wrapping.

    I wonder, on the other hand, how would >2TB disks behave under Dynamic Disks. Theoretically, it completely replaces all common partitioning layout…

    Just things to think about…
    Ez

  30. Nev Says:

    The above procedure works well for when adding new physical disks into the array.
    What about this scenario .. say you have 6 x 300GB SAS drives in RAID-10 configuration .. which works out to an effective available capacity of about 900GB. Say over time, each drive dies one at a time and you replace them with 600GB drives, until eventually all 6 drives have been replaced with 600GB drives – but the logical size will still only be 900GB. How to you expand the size of the logical volume to use the entire 600GB of each disk, therefore doubling the available disk space?

  31. ez-aton Says:

    To be honest – I have no idea. It would have to deal with the RAID-level and not the Logical Unit (LUN) level. I believe that there are some (hidden?) commands to handle the physical layer layout changes, however maybe you could add an additional disk (the 7th) and force the system to rebalance its store. It’s nothing more than a guess, though.

    Ez

  32. Sree Says:

    Hi Friends,

    We need to expand one LUN on an Array. But we dont have any free space on the same raid group. Can we use free space on another raid group to expand this LUN?

  33. etzion Says:

    No. LUNs cannot span over multiple RAID groups. Sorry. You will play the (un)enjoyable game of data migration.
    Sorry….

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