SNapshot to a different datastore

[EkilErif]

Hi,

Quick question for the community.

Assume I have 2 datastores and virtual machine A sits in datastore 1. Can I take a snapshot of the machine and have this snapshot reside on datastore 2?

My understanding was I could not easily do this but our service provider says that is the way it works and I am trying to find a documented, supported method of doing this.

Any responses will be appreciated.

Kind regards

Richard

[geddam]

Snapshots should reside in same folder as VM....Snapshots cannot but placed under a different datastore.

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful

[lamw · Accepted solution]

Incorrect, it's best practice and it defaults to storing snapshots in the same datastore in which the VMDK resides in, but it does not have to.

You can modify VM's .vmx to store snapshots on a different datastore, this can be useful if you're running out of space on the datastore in which your VM resides in.

Please refer to this VMware KB on configuring this change: http://kb.vmware.com/kb/1002929

=========================================================================

William Lam

VMware vExpert 2009

VMware ESX/ESXi scripts and resources at:

Twitter: @lamw

VMware Code Central - Scripts/Sample code for Developers and Administrators

VMware Developer Community

If you find this information useful, please award points for "correct" or "helpful".

[geddam]

I dont agree to this comment...Keeping snapshots in same directory is default and is a best practice for snapshot chaining and performance. KB is for editing VMX file manually and placing snapshots accordingly (and above this KB is limited to ESX 3.0.X)...And by any chance, if a snapshot chain is broken under specific conditions...you will be having a tough time re-creating snapshot chain and committing them.

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful

[lamw]

You're pretty much repeating what I had just said, I agree, you should not be modifying this value but if you understand the change, you can modify. Your initial reply stated, that you can't change this behavior and that is incorrect. Also if you take a look at the KB, there are valid reasons on changing the behavior such as a datastore being full and needing to take a snapshot. The KB refers to 3.x but this also works under 4.x, VMware's doc isn't always known to be up to date

=========================================================================

William Lam

VMware vExpert 2009

VMware ESX/ESXi scripts and resources at:

Twitter: @lamw

VMware Code Central - Scripts/Sample code for Developers and Administrators

VMware Developer Community

If you find this information useful, please award points for "correct" or "helpful".

[geddam]

When you file a support request with VMware, it is always said, editing

vmx file is not supported,. KB strategy was bad before but not now....All KBs now a day carry version info as mandatory title.

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful

[lamw]

Well it's not unheard of that their support organization is not in sync with their documentation, it's not the first time I've seen this either.

Here is a great example from Jason Boche's experience http://www.boche.net/blog/index.php/2010/02/12/vmkernel-networks-jumbo-frames-and-esxi/ and it's with BCS support! (If you're not familiar with BCS, it's the highest level of support from VMware, higher than platinum) and he got the round-about from support and the docs.

My point being, their docs aren't always up to date. I've personally just tested this on ESXi 4.0 host and the .vmx modification and it does indeed works.

Now back to the original point on whether or not someone should be modifying this value, I totally agree 100% that user's should not be modifying this value, the default behavior of storing snapshots with the VMDK(s) is definitely a best practices and yes bad things can potentially occur if you modify it otherwise. Though if a user totally understands, then he/she can decide on making this change. Probably good idea to contact VMware Support to ensure you'll still be under support, but for those that don't have SnS, then it's really a personal decision.

=========================================================================

William Lam

VMware vExpert 2009

VMware ESX/ESXi scripts and resources at:

Twitter: @lamw

VMware Code Central - Scripts/Sample code for Developers and Administrators

VMware Developer Community

If you find this information useful, please award points for "correct" or "helpful".

[EkilErif]

Brilliant thanks for all the info guys I really appreciate it!

Richard

[geddam]

Cool, Now I am in sync with you LamW...Nice explaination.

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful