vsphere and Nas windows 2008 storage

[ehermouet44]

Hi all,

currently we have 2 esx vsphere server, and 1 nas HP x1400. the 2 esx have 4 gigabit network card, and the nas have 2 gigabits network drive.

esx 1 have 45gb ram, 16 processors

esx 2 have 24 gb ram, 8 processors

nas 4 processors and 6 gb of ram.

vsphere 4.1 is installed.

everithing work, with total of 12 vm server. but we have big problem. When we want to create new machine or new virtual disk, and when the virtual disk ir more than 180 gb (approx) nas serveur use all drive acces to create it, next the 2 esx lost connexion with it, and my vm server freeze, and next shutdown.

i search a mean to stop this. sometime when my nas use some drive access, it 's the same result with 4 or 5 sec of lost connexion on the vmservers.

any body can help me ?

[Shakaal]

Hi,

Would request you to open a putty(ssh) session to the esx host on which you are creating the VM, and run esxtop command. now press d this will take you to the disk panel where you will be able to see Disk performance activity, check for DAVG parameter and post the value, it shouldnt be more than 15 in case of FC SAN, incase of NAS it can be fine upto 30 to 40 but more value can be an issue, Causing problems as mentioned by you

Regards

[ehermouet44]

Hi tks for your reply,

it's appreciated.

we have 42 sometimes, but not every sec.

i can't try to create disk now because i will block my customers.

if it's this, do you know issue to correct it ?

[Shakaal]

Hi,

is this a physical NAS box or a VM.

regards

[ehermouet44]

this is physical nas, HP storagewoks nx1400.

[harrygunter]

How many disks has this NAS box got?

This is usually always the main performance problem with disk subsystems, not enough spindles to generate the I/O required by the VM,s

[Shakaal]

Hi,

whenever the value for DAVG is going high, it means that box is unable to handle the IO. check with HP  if they can optimize the storage for the kind of IO's.

also can u run esxtop in batch mode create a disk and upload that batch log to the portal so that i can check few more things on storage part.

Please refer to following link for batch mode execution of esxtop

www.yellow-bricks.com/esxtop

Regards

[ehermouet44]

there is 4 disques of 2Tb/disk on raid 5.

[harrygunter]

4 disks and they are SATA? @ 7200rpm you will never acheive very good performnace with that I'm afraid.

Only thing to do is not provision new guests during worktime or add another shelf with more disks to increase the I/O.

Mark