Increasing VMFS Volume

[raxz]

Hi All,

I am trying to extend/increase an existing local storage VMFS volume. I have got an unused 500GB volume, that I would like to add to my existing 1.82 TB VMFS volume.

I can see the extra volume available on the system using fdisk command, and I can also add this extra volume as separate datastore, but when I try increasing the existing data store, I do not see this extra volume available in the list of available LUNs.

Please check below my the physical storage on the box:

# fdisk -lu

Disk /dev/cciss/c0d0: 2000.3 GB, 2000342441984 bytes

255 heads, 63 sectors/track, 243194 cylinders, total 3906918832 sectors

Units = sectors of 1 * 512 = 512 bytes

Device Boot Start End Blocks Id System

/dev/cciss/c0d0p1 * 63 2249099 1124518+ 83 Linux

/dev/cciss/c0d0p2 2249100 2474009 112455 fc VMware VMKCORE

/dev/cciss/c0d0p3 2474010 3906911609 1952218800 5 Extended

/dev/cciss/c0d0p5 2474073 3906911609 1952218768+ fb VMware VMFS

Disk /dev/cciss/c0d1: 500.0 GB, 500074307584 bytes

255 heads, 63 sectors/track, 60797 cylinders, total 976707632 sectors

Units = sectors of 1 * 512 = 512 bytes

Device Boot Start End Blocks Id System

Disk /dev/sda: 17.3 GB, 17308844032 bytes

255 heads, 63 sectors/track, 2104 cylinders, total 33806336 sectors

Units = sectors of 1 * 512 = 512 bytes

Device Boot Start End Blocks Id System

/dev/sda1 63 8193149 4096543+ 83 Linux

/dev/sda2 8193150 11261564 1534207+ 82 Linux swap / Solaris

/dev/sda3 11261565 33800759 11269597+ 5 Extended

/dev/sda5 11261628 15358139 2048256 83 Linux

/dev/sda6 15358203 19454714 2048256 83 Linux

/dev/sda7 19454778 23551289 2048256 83 Linux

/dev/sda8 23551353 33800759 5124703+ 83 Linux

# esxcfg-scsidevs -c

Device UID Device Type Console Device Size Plugin Display Name

mpx.vmhba0:C0:T0:L0 Direct-Access /dev/cciss/c0d0 1907675MB NMP Local VMware Disk (mpx.vmhba0:C0:T0:L0)

mpx.vmhba0:C0:T1:L0 Direct-Access /dev/cciss/c0d1 476908MB NMP Local VMware Disk (mpx.vmhba0:C0:T1:L0)

mpx.vmhba1:C0:T0:L0 CD-ROM /dev/sr0

# esxcli nmp device list

Device Display Name: Local VMware Disk (mpx.vmhba0:C0:T1:L0)

Storage Array Type: VMW_SATP_LOCAL

Storage Array Type Device Config:

Path Selection Policy: VMW_PSP_FIXED

Path Selection Policy Device Config: {preferred=vmhba0:C0:T1:L0;current=vmhba0:C0:T1:L0}

Working Paths: vmhba0:C0:T1:L0

mpx.vmhba1:C0:T0:L0

Device Display Name: Local TSSTcorp CD-ROM (mpx.vmhba1:C0:T0:L0)

Storage Array Type: VMW_SATP_LOCAL

Storage Array Type Device Config:

Path Selection Policy: VMW_PSP_FIXED

Path Selection Policy Device Config: {preferred=vmhba1:C0:T0:L0;current=vmhba1:C0:T0:L0}

Working Paths: vmhba1:C0:T0:L0

mpx.vmhba0:C0:T0:L0

Device Display Name: Local VMware Disk (mpx.vmhba0:C0:T0:L0)

Storage Array Type: VMW_SATP_LOCAL

Storage Array Type Device Config:

Path Selection Policy: VMW_PSP_FIXED

Path Selection Policy Device Config: {preferred=vmhba0:C0:T0:L0;current=vmhba0:C0:T0:L0}

Working Paths: vmhba0:C0:T0:L0

0MB NMP Local TSSTcorp CD-ROM (mpx.vmhba1:C0:T0:L0)

I would like to find out why am I not being able to add "/dev/cciss/c0d1" as an extent to existing VMFS volume?

Regards

[RParker]

> 500GB volume, that I would like to add to my existing 1.82 TB VMFS volume

There is your mistake, 500GB + 1.82 TB = 2.32 TB, which can NOT be done on a VMFS volume, it has to be LESS than 2 TB.

So therefore you are basically stuck with what you have, you can make it a NEW VMFS volume but you can't grow it.. unless you use an extent, which is not recommended...

[raxz]

Hi,

Well spotted.

I was basically trying to add an extent and on ESX 3.5 that's how one would add an extent.

How can I add this extra storage as an extent to existing VMFS storage?

I will have to add an extent because I am using this storage as a target storage for replication job running by VEEAM for DR.

Regards

[RParker]

Well the other problem is the space has to be a part of a SEPARATE drive / partition.

So if you have a 4 TB drive / array, and you set the VMFS as 2TB on that same drive, you will lose ALL the drive space, because ESX can only "see" 2TB. So you may be able to see it with fdisk, but if the space is part of the original partition where you installed ESX / VMFS volume you can't ADD it as an extent.

So short answer, you are stuck with what you have.

If you reconfigure the machine to make 2 distinct drives / arrays (1 2TB and 1 500 GB) THEN it will work, but as you have it now, you are basically hitting the wall.

[lazyllama]

I think you may need to partition the disk manually before ESX will recognise it as usable for the extent.

At the moment , fdisk shows no partitions on that disk.

http://kb.vmware.com/kb/1008938 gives details on using fdisk to do the partitioning.

[raxz]

Hi "RParker"

This is a separate volume/disk. There are 2 volumes on this host one as RAID10 and one as RAID1. ESX installation is on RAID10 existing VMFS volume. I am trying to add other RAID1 to existing VMFS storage as an extent.

Thanks

[raxz]

Hi "lazyllama"

I tried this earlier as I thought that I would need a partition on the disks. I created a primary partition numbered "1" using all available space on that disk with file system 83(Linux).

I am happy to go ahead with the partitioning, shall I use 83 or fb to format the partition as VMFS?

Am I OK to partition the disk as primary partition 1?

Once I have made the partition, do I need to use vmkfstools utility to create the extent or can this be done from VI client?

Regards

[lazyllama]

The partition ID should be 'fb' for VMFS and a single primary partition should be fine.

That KB article also has steps to make sure the alignment is correct.

Once you've done that, do a rescan and re-try adding the extent. If that doesn't work, try the rest of the steps from the KB article to use vmkfstools to create the file system on the partition.

[raxz]

Hi "lazyllama"

Thanks for your feedback.

I have managed to extend the volume by using fdisk and vmkfstools commands from CLI. I did not find much information on KB regarding alignment, but I followed another article where it explains about 64k boundary alignment and using extended fdisk command "r" with value 128.

My volume is now extended and got some room to breath.

Now next question comes to mind, can we remove an extent as well, of its an irreversible process?

Regards

[lazyllama]

Sorry, my mistake on the alignment thing, I had two KB articles open in my browser, only one had the alignment info. Glad you got that sorted.

As far as I can see, removing an extent isn't possible, or at least it's not advisable as you have no control over what data is placed in which extent.

In theory you could Storage VMotion all your VMs off the datastore, and then remove the extent, but you may as well destroy it and re-create it if you're going down that route.

[raxz]

This sounds reasonable.

How would you check extents on the ESX host? I mean what command would

show the extent details?

I came across this http://glandium.org/blog/?p=513 regarding removing

extents, but again this would be risky, and not something advised by

VMWARE.

Regards

[lazyllama]

Yes, I'd be very wary of using 3rd party tools on my VMFS file systems, particularly if any data was involved :smileyshocked:

vmkfstools -Ph /vmfs/volumes/<vmfsvolname>

will list the extents that make up a volume, along with other info:

VMFS-3.31 file system spanning 1 partitions.

File system label (if any): vmfsvol1OnGS2-1eqlgroup

Mode: public

Capacity 2.0T, 1.1T available, file block size 2.0M

UUID: 47fcf644-443850f6-51ae-001a64362cb0

Partitions spanned (on "lvm"):

vmhba2:0:0:1

I hope that's of use to you.

[raxz]

Thanks lazyllam for all your replies.

I guess we can close this discussion now.

Regards