Is there a limit to the number of VM's per NFS export?

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Is there a limit to the number of VM's per NFS export?

by Page, Jeremy :: Rate this Message:

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For the folks using NFS to hold their VMDK files, have you run into a limit to how many VM’s a  single share can support? Either a hard limit or just a point where performance degrades? I’m trying to figure out how many volumes I’ll need to create to hold ~300 VMs on my 3070 cluster.

 

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RE: Is there a limit to the number of VM's per NFS export?

by King, Robert :: Rate this Message:

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See the above TR for best practices with VMWare ESX.  Lun alignment is crucial to performance with an environment that has many VMDK's.

From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 7:10 AM
To: toasters@...
Subject: Is there a limit to the number of VM's per NFS export?

For the folks using NFS to hold their VMDK files, have you run into a limit to how many VM’s a  single share can support? Either a hard limit or just a point where performance degrades? I’m trying to figure out how many volumes I’ll need to create to hold ~300 VMs on my 3070 cluster.

 

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
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recipient, please notify the sender immediately by responding to
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RE: Is there a limit to the number of VM's per NFS export?

by Page, Jeremy :: Rate this Message:

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I’m not using LUNs, I’m using NFS, which unfortunately is not very well covered in that document.

 

Jeremy M. Page____________________            

Systems Architect

* email:Jeremy.Page@... - ( phone: 336.547.5399 - 6 fax: 336.547.5163 - ( cell: 336.601.7274


From: King, Robert [mailto:Robert.King@...]
Sent: Wednesday, May 28, 2008 8:29 AM
To: Page, Jeremy; toasters@...
Subject: RE: Is there a limit to the number of VM's per NFS export?

 

http://media.netapp.com/documents/tr-3428.pdf

See the above TR for best practices with VMWare ESX.  Lun alignment is crucial to performance with an environment that has many VMDK's.


From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 7:10 AM
To: toasters@...
Subject: Is there a limit to the number of VM's per NFS export?

For the folks using NFS to hold their VMDK files, have you run into a limit to how many VM’s a  single share can support? Either a hard limit or just a point where performance degrades? I’m trying to figure out how many volumes I’ll need to create to hold ~300 VMs on my 3070 cluster.

 

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
recipient, please notify the sender immediately by responding to
this e-mail, and delete the message from your system. If you
have any questions about this e-mail please notify the sender
immediately.

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
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have any questions about this e-mail please notify the sender
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RE: Is there a limit to the number of VM's per NFS export?

by King, Robert :: Rate this Message:

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Some parts of this message have been removed. Learn more about Nabble's security policy.
There is a section that covers offset's for the vmdk's.  This is particularly important when implementing vmdk's in order to avoid partial writes.


From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 8:41 AM
To: King, Robert; toasters@...
Subject: RE: Is there a limit to the number of VM's per NFS export?

I’m not using LUNs, I’m using NFS, which unfortunately is not very well covered in that document.

 

Jeremy M. Page____________________            

Systems Architect

* email:Jeremy.Page@... - ( phone: 336.547.5399 - 6 fax: 336.547.5163 - ( cell: 336.601.7274


From: King, Robert [mailto:Robert.King@...]
Sent: Wednesday, May 28, 2008 8:29 AM
To: Page, Jeremy; toasters@...
Subject: RE: Is there a limit to the number of VM's per NFS export?

 

http://media.netapp.com/documents/tr-3428.pdf

See the above TR for best practices with VMWare ESX.  Lun alignment is crucial to performance with an environment that has many VMDK's.


From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 7:10 AM
To: toasters@...
Subject: Is there a limit to the number of VM's per NFS export?

For the folks using NFS to hold their VMDK files, have you run into a limit to how many VM’s a  single share can support? Either a hard limit or just a point where performance degrades? I’m trying to figure out how many volumes I’ll need to create to hold ~300 VMs on my 3070 cluster.

 

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
recipient, please notify the sender immediately by responding to
this e-mail, and delete the message from your system. If you
have any questions about this e-mail please notify the sender
immediately.

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
recipient, please notify the sender immediately by responding to
this e-mail, and delete the message from your system. If you
have any questions about this e-mail please notify the sender
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RE: Is there a limit to the number of VM's per NFS export?

by Webster, Stetson :: Rate this Message:

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I think you will want to address this in terms of the 'ops'.  Start with ensuring that you are employing all the NFS best practices and make sure your NFS host (in this case the filer) scales to the load you intend.
 

Stetson M. Webster
Onsite Professional Services Engineer
PS - North Amer. - East

NetApp
919.250.0052 Mobile
Stetson.Webster@...

 


From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 8:41 AM
To: King, Robert; toasters@...
Subject: RE: Is there a limit to the number of VM's per NFS export?

I’m not using LUNs, I’m using NFS, which unfortunately is not very well covered in that document.

 

Jeremy M. Page____________________            

Systems Architect

* email:Jeremy.Page@... - ( phone: 336.547.5399 - 6 fax: 336.547.5163 - ( cell: 336.601.7274


From: King, Robert [mailto:Robert.King@...]
Sent: Wednesday, May 28, 2008 8:29 AM
To: Page, Jeremy; toasters@...
Subject: RE: Is there a limit to the number of VM's per NFS export?

 

http://media.netapp.com/documents/tr-3428.pdf

See the above TR for best practices with VMWare ESX.  Lun alignment is crucial to performance with an environment that has many VMDK's.


From: Page, Jeremy [mailto:jeremy.page@...]
Sent: Wednesday, May 28, 2008 7:10 AM
To: toasters@...
Subject: Is there a limit to the number of VM's per NFS export?

For the folks using NFS to hold their VMDK files, have you run into a limit to how many VM’s a  single share can support? Either a hard limit or just a point where performance degrades? I’m trying to figure out how many volumes I’ll need to create to hold ~300 VMs on my 3070 cluster.

 

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
recipient, please notify the sender immediately by responding to
this e-mail, and delete the message from your system. If you
have any questions about this e-mail please notify the sender
immediately.

This message (including any attachments) contains confidential
and/or proprietary information intended only for the addressee.
Any unauthorized disclosure, copying, distribution or reliance on
the contents of this information is strictly prohibited and may
constitute a violation of law. If you are not the intended
recipient, please notify the sender immediately by responding to
this e-mail, and delete the message from your system. If you
have any questions about this e-mail please notify the sender
immediately.



Re: Is there a limit to the number of VM's per NFS export?

by Stephen C. Losen :: Rate this Message:

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> I'm not using LUNs, I'm using NFS, which unfortunately is not very well
> covered in that document.
>
>  
>
> From: Page, Jeremy [mailto:jeremy.page@...]
> Sent: Wednesday, May 28, 2008 7:10 AM
> To: toasters@...
> Subject: Is there a limit to the number of VM's per NFS export?
>
> For the folks using NFS to hold their VMDK files, have you run into a
> limit to how many VM's a  single share can support? Either a hard limit
> or just a point where performance degrades? I'm trying to figure out how
> many volumes I'll need to create to hold ~300 VMs on my 3070 cluster.
>

Using multiple volumes is more for snapshot and dedupe management, since
these are volume wide operations.

I don't think that there is any need to split VMDKs over multiple
volumes simply for NFS performance reasons.

From what I've heard/read you should have (at least) three volumes, each with
a different snapshot/dedupe configuration.  Each VM will have some of
its VMDKs in each of these volumes, so each VM has at least 3 VMDKs.

One volume should be for VMDKs that hold swap space and temporary files.
This volume should not have snapshots enabled.  Since swap space is highly
volatile, and never needs to be restored, mixing it with less volatile data
in the same volume needlessly consumes snapshot space. It probably doesn't
pay to deduplicate this volume either.

One volume should be for VMDKs to hold the guest OS install. This volume
should have snapshots enabled, but perhaps not very often.  This volume
should definitely use deduplication since you will probably be installing
the same guest OS on very many VMs.

One volume should be for VMDKs that hold VM local software and data.
This volume should have snapshots enabled to occur more frequently, since
this is the data that will most likely need to be restored from snapshots.

Steve Losen   scl@...    phone: 434-924-0640

University of Virginia               ITC Unix Support