Tuesday, November 8, 2011

ESXi Storage Add Issue..Call fails for “HostDatastoreSystem.QueryVmfsDatastore- CreateOptions” for object “ha-datastoresystem”

Solution
Source VMWARE.

Clearing partitioning information in ESXi using the DD utility

Due to differences between ESX classic and ESXi, the parted utility is not available in ESXi. These steps describe how to clear partitioning information for a LUN under ESXi.
Warning: This process will destroy data on the target device. The steps outlined here are potentially hazardous for your environment if they are not followed exactly. If you are not comfortable performing these steps, contact VMware Technical Support and work with them to resolve the issue.
  1. Open a console to the ESX or ESXi host.

  2. Identify the disk device in question from the log messages. For example:

    /vmfs/devices/disks/vml.0200030000600508b30093fcf0a05b5b8cc739002f4d5341313531
     
  3. Use the fdisk command to obtain the exact size of the target disk device in bytes:

    fdisk -l "/vmfs/devices/disks/DeviceName"

    The output appears similar to:

    Disk /vmfs/devices/disks/DeviceName: 536 MB, 429491220480 bytes
    255 heads, 63 sectors/track, 52216 cylinders, total 838850040 sectors
    Units = sectors of 1 * 512 = 512 bytes

                            Device Boot    Start          End    Blocks   Id  System
    /vmfs/devices/disks/DeviceName             1 128838850039 419424956   ee  EFI GPT

  4. Use the dd command to erase the first 34 sectors (34x512 bytes) of the disk device with zeros:

    dd if=/dev/zero of="/vmfs/devices/disks/DeviceName" bs=512 count=34 conv=notrunc

    Caution: This operation deletes the partition table and master boot record on the disk device. The changes take effect immediately. This results in data loss and cannot be reverted.
     
  5. The GPT partition scheme stores a backup of the partition table at the end of the disk device. Erase the last 34 sectors of the device as well:

    1. Determine the offset at which the last 34 sectors begins:

      (SizeInBytes / 512) - 34 = SeekOffset

      For example, using the values in step 3:

      (429491220480 / 512) - 34 = 838850006

    2. Use the dd command to erase the last 34 sectors of the disk, starting at the offset found in step 5a:

      dd if=/dev/zero of="/vmfs/devices/disks/DeviceName" bs=512 count=34 seek=SeekOffset conv=notrunc

      Caution: This operation deletes the partition table and master boot record on the disk device. The changes take effect immediately. This results in data loss and cannot be reverted.

  6. Depending on the original contents of the disk device, it may be necessary to erase a larger amount of data on the disk.

  7. Retry the storage operation.
Few more that I stumbled on Google
http://www.eversity.nl/blog/2010/08/call-fails-for-hostdatastoresystem-queryvmfsdatastore-createoptions-for-object-ha-datastoresystem/

http://www.digital52.com/help/gptremoval.html


ESXi 5.0 Issue with ISP2432 HBA

So if you are upgrading to ESXi 5.0 and have these HBAs, they are not supported. Doing a Rescan will not pick up the newly provided LUNs.
We have to issue a LIP to get the LUNs seen which is disruptive to the IO.

~ # echo "scsi-qlalip" > /proc/scsi/qla2xxx/5
~ # echo "scsi-qlalip" > /proc/scsi/qla2xxx/6
~ #

boxgrinder- Cool Stuff

http://boxgrinder.org/

Saturday, October 8, 2011

ext3/ext4-Performance-RHEL 6

EMC Backend AX4-5F. RAID-10 12 600G 1k Drives in 4G Qlogic Fibre.

So what does dd does on the  ext3 filesystems and ext4 ones. with 8MB block size

dd if=/dev/zero of=aman2 bs=8192 count=1000000
1000000+0 records in
1000000+0 records out
8192000000 bytes (8.2 GB) copied, 8.50084 s, 964 MB/s

4MB block

dd if=/dev/zero of=aman2 bs=4192 count=1000000
1000000+0 records in
1000000+0 records out
4192000000 bytes (4.2 GB) copied, 6.19781 s, 676 MB/s



Now with ext3

 dd if=/dev/zero of=aman3 bs=8192 count=1000000
1000000+0 records in
1000000+0 records out
8192000000 bytes (8.2 GB) copied, 13.7891 s, 594 MB/s

iostat is still active after these 13 secs flushing data to the disk

10/08/2011 02:23:49 PM
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
           0.00    0.00    2.56   10.57    0.00   86.88

Device:            tps   Blk_read/s   Blk_wrtn/s   Blk_read   Blk_wrtn
sda               0.00         0.00         0.00          0          0
sdb            4790.00         0.00    101200.00          0     101200
sdd            5272.00         0.00    103056.00          0     103056
sde               0.00         0.00         0.00          0          0
sdc               0.00         0.00         0.00          0          0
emcpowera     10063.00         0.00    204256.00          0     204256
dm-0          43984.00         0.00    351872.00          0     351872

Seems like ext4 is beating the hell out of ext3.Althoigh dd is not a pure performance testing but it gives  a little pinch as to what to expect.