Awesome. Thank you sir!

On Feb 4, 2013, at 2:54 PM, Sebastian Goetze spgoetze@gmail.com wrote:

Hi Scott,

the online alignment happens by storage-vMotioning the mis-aligned VM into a 'reverse-misaligned' VMFS-datastore. Thereby the two mis-alignments will cancel each other out and your VM is aligned.

A NFS datastore can't be misaligned. (But the VMDKs *in* it can...) So no way of using a NFS datastore to compensate for mis-alignment.

Also, as soon as you vMotion the VM away from the (correct) 'reverse-misaligned' datastore, your VM will be misaligned again, since you loose the compensation.

Solution: Do an offline alignment. Then your free to vMotion where-ever you like to (as long as the datastore is correctly aligned).

OK?

Sebastian

On 04.02.2013 20:41, Scott Eno wrote:

...

Hi,

We're trying to get some VM's aligned in our NFS-based VMware environment using the "online" alignment tool packaged in VSC. Since we are NFS, the tool needs a VMFS datastore to use to align the VM. When we run the tool and it moves the VM to the VMFS datastore, the VM no longer shows up as misaligned.

However, if we move the VM back to an NFS datastore, it shows up as misaligned again.

So, is this a one-way trip? NFS --> VMFS, but that VM can never go back? _______________________________________________ Toasters mailing list Toasters@teaparty.net http://www.teaparty.net/mailman/listinfo/toasters

Thank you Peter!

So these "shimmed" datastores are only for mis-aligned VM's correct? Would an "aligned" VM become "unaligned" if placed in these datastores? Other non-Vm data probably wouldn't perform well in a "shimmed" datastore either, I would guess.

On Feb 4, 2013, at 3:13 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

Hi Scott. VSC 4.1 supports "shimmed" or aligned datastores with NFS, but for initial deployments we're requiring a PVR (basically special permission so we can track who's using it). Your NetApp SE can get this for you, then you'll get the information to activate the feature.

Not that moving the VM into a shimmed or offset datastore doesn't actually fix the VM - it basically uses a datastore that is offset by the same amount as the VM, but in the opposite direction (or 8's complement if you like). With VMFS, the LUN is offset. With NFS, there's a feature in which files with certain extensions get offset in the WAFL volume.

If you move a VM into a datastore with a different offset (or no offset and the VM itself was never realigned), the I/O will be misaligned again.

I hope this helps!

Peter

-----Original Message----- From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Scott Eno Sent: Monday, February 04, 2013 11:42 AM To: Toasters Subject: VSC 4.1 & Online alignments

Hi,

We're trying to get some VM's aligned in our NFS-based VMware environment using the "online" alignment tool packaged in VSC. Since we are NFS, the tool needs a VMFS datastore to use to align the VM. When we run the tool and it moves the VM to the VMFS datastore, the VM no longer shows up as misaligned.

However, if we move the VM back to an NFS datastore, it shows up as misaligned again.

So, is this a one-way trip? NFS --> VMFS, but that VM can never go back? _______________________________________________ Toasters mailing list Toasters@teaparty.net http://www.teaparty.net/mailman/listinfo/toasters

Our situation, for the most part, works with this temporary solution as we have some RHEL3 servers that were P2V'd. They are mis-aligned, and when aligned won't boot, so this solution works for this handful of systems until they are replaced in the near future.

On Feb 4, 2013, at 6:22 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

That is correct. Move a VM that was already aligned (either correct in the first place like Win 2008 or fixed by mbralign, VMware Converter, etc.) into an aligned/shimmed/offset datastore, and the resulting I/O will be misaligned.

Alon's comments are also correct - this is intended as a short-term fix. Actual alignment of the VM (using mbralign, VMware Converter, vOptimizer, PlateSpin, Paragon) is a better long-term solution. We realize that once the pain goes away, people tend not to deal with the underlying issue, so some people will simply use the shimmed datastores long term.

Peter

-----Original Message----- From: Scott Eno [mailto:s.eno@me.com] Sent: Monday, February 04, 2013 12:58 PM To: Learmonth, Peter Cc: Scott Eno; Toasters Subject: Re: VSC 4.1 & Online alignments

Thank you Peter!

So these "shimmed" datastores are only for mis-aligned VM's correct? Would an "aligned" VM become "unaligned" if placed in these datastores? Other non-Vm data probably wouldn't perform well in a "shimmed" datastore either, I would guess.

On Feb 4, 2013, at 3:13 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

...

Hi Scott. VSC 4.1 supports "shimmed" or aligned datastores with NFS, but for initial deployments we're requiring a PVR (basically special permission so we can track who's using it). Your NetApp SE can get this for you, then you'll get the information to activate the feature.

Not that moving the VM into a shimmed or offset datastore doesn't actually fix the VM - it basically uses a datastore that is offset by the same amount as the VM, but in the opposite direction (or 8's complement if you like). With VMFS, the LUN is offset. With NFS, there's a feature in which files with certain extensions get offset in the WAFL volume.

If you move a VM into a datastore with a different offset (or no offset and the VM itself was never realigned), the I/O will be misaligned again.

I hope this helps!

Peter

-----Original Message----- From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Scott Eno Sent: Monday, February 04, 2013 11:42 AM To: Toasters Subject: VSC 4.1 & Online alignments

Hi,

We're trying to get some VM's aligned in our NFS-based VMware environment using the "online" alignment tool packaged in VSC. Since we are NFS, the tool needs a VMFS datastore to use to align the VM. When we run the tool and it moves the VM to the VMFS datastore, the VM no longer shows up as misaligned.

However, if we move the VM back to an NFS datastore, it shows up as misaligned again.

So, is this a one-way trip? NFS --> VMFS, but that VM can never go back? _______________________________________________ Toasters mailing list Toasters@teaparty.net http://www.teaparty.net/mailman/listinfo/toasters

Yep, we do the grub fix on all the Linux vm's we realign, but something's wacky* about these old RHEL3 P2V's.

* technical term used by some storage admins. See also: thingy, doohickey, and "hmmm, that's odd."

---- Scott Eno s.eno@me.com

On Feb 4, 2013, at 8:11 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

When you say "won't boot", did you apply the GRUB fix as documented in TR-3747?

Peter

-----Original Message----- From: Scott Eno [mailto:s.eno@me.com] Sent: Monday, February 04, 2013 5:09 PM To: Learmonth, Peter Cc: Scott Eno; Toasters Subject: Re: VSC 4.1 & Online alignments

Our situation, for the most part, works with this temporary solution as we have some RHEL3 servers that were P2V'd. They are mis-aligned, and when aligned won't boot, so this solution works for this handful of systems until they are replaced in the near future.

On Feb 4, 2013, at 6:22 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

...

That is correct. Move a VM that was already aligned (either correct in the first place like Win 2008 or fixed by mbralign, VMware Converter, etc.) into an aligned/shimmed/offset datastore, and the resulting I/O will be misaligned.

Alon's comments are also correct - this is intended as a short-term fix. Actual alignment of the VM (using mbralign, VMware Converter, vOptimizer, PlateSpin, Paragon) is a better long-term solution. We realize that once the pain goes away, people tend not to deal with the underlying issue, so some people will simply use the shimmed datastores long term.

Peter

-----Original Message----- From: Scott Eno [mailto:s.eno@me.com] Sent: Monday, February 04, 2013 12:58 PM To: Learmonth, Peter Cc: Scott Eno; Toasters Subject: Re: VSC 4.1 & Online alignments

Thank you Peter!

So these "shimmed" datastores are only for mis-aligned VM's correct? Would an "aligned" VM become "unaligned" if placed in these datastores? Other non-Vm data probably wouldn't perform well in a "shimmed" datastore either, I would guess.

On Feb 4, 2013, at 3:13 PM, "Learmonth, Peter" Peter.Learmonth@netapp.com wrote:

...

Hi Scott. VSC 4.1 supports "shimmed" or aligned datastores with NFS, but for initial deployments we're requiring a PVR (basically special permission so we can track who's using it). Your NetApp SE can get this for you, then you'll get the information to activate the feature.

Not that moving the VM into a shimmed or offset datastore doesn't actually fix the VM - it basically uses a datastore that is offset by the same amount as the VM, but in the opposite direction (or 8's complement if you like). With VMFS, the LUN is offset. With NFS, there's a feature in which files with certain extensions get offset in the WAFL volume.

If you move a VM into a datastore with a different offset (or no offset and the VM itself was never realigned), the I/O will be misaligned again.

I hope this helps!

Peter

-----Original Message----- From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Scott Eno Sent: Monday, February 04, 2013 11:42 AM To: Toasters Subject: VSC 4.1 & Online alignments

Hi,

We're trying to get some VM's aligned in our NFS-based VMware environment using the "online" alignment tool packaged in VSC. Since we are NFS, the tool needs a VMFS datastore to use to align the VM. When we run the tool and it moves the VM to the VMFS datastore, the VM no longer shows up as misaligned.

However, if we move the VM back to an NFS datastore, it shows up as misaligned again.

So, is this a one-way trip? NFS --> VMFS, but that VM can never go back? _______________________________________________ Toasters mailing list Toasters@teaparty.net http://www.teaparty.net/mailman/listinfo/toasters