VMware Solutions Discussions

VMware SRM for vSphere and NFS


[cross-posted from The Virtualization Effect blog - http://blogs.netapp.com/virtualization/2009/10/vmware-srm-for-vsphere-and-nfs.html]

Posted by Larry Touchette – Technical Marketing Engineer, Server Virtualization

This week VMware released a new version of SRM to support vSphere environments.  This release of SRM brings the long awaited support for NFS environments.

Major New Features

NFS Support! – Customers who decided to take advantage of the NFS protocol will now be able to enhance their DR capabilities using SRM, getting quicker RTO times and the ability to fully automate recovery of NFS datastores and the virtual machines in them quickly and easily.

Shared Recovery Sites – SRM 4.0 also brings a new feature called shared recovery sites.  This feature allows multiple sites to be protected with one shared DR site.  This model requires a vCenter and SRM server in each protected site and single vCenter server in the DR site, with multiple SRM servers, one for each protected site.


To keep in sequence with vSphere versioning VMware decided to call this release SRM 4.0. 

  • NFS support requires SRM 4.0, which requires vCenter 4.0, so NFS customers on VI3 will have to upgrade to vSphere (vCenter 4.0) in order to support NFS.  SRM 4.0 supports ESX hosts running ESX 3.0.3, ESX/ESXi 3.5U3+ or 4.0 so if you're running one of these versions of ESX there's no requirement to upgrade those for NFS support.
  • NetApp is releasing separate storage recovery adapters, SRA, one for SAN and one for NAS.  The NAS adapter supports virtual machines having data in NFS datastores and the SAN adapter supports virtual machines having data in iSCSI and/or FCP datastores.

The following table describes the version requirements for the NetApp adapters.


NFS Capabilities

Many customers have implemented multiple private storage networks in VMware on NFS environments like those describe in the network section of TR-3749VMware and NetApp had to work closely together to ensure support for these network designs in SRM and I co-presented on the subject with VMware in session BC3210 at VMworld 2009 in San Francisco.  Here’s a simple example of a VMware on NFS environment where the NetApp controller is using two IP addresses to server NFS data to clients.

Dual NFS networks

To support private storage networks the NetApp NAS adapter adds a new field to the configuration of the array in SRM array managers.  This field, called NFS IP Addresses, collects the IP addresses on the NetApp array that are used to connect to when mounting NFS datastores.  As the SRM administrator you enter all the IP addresses, comma separated, in this field.

NFS Array manager

When SRM is performing a DR test or failover it will mount datastores in a round-robin fashion, the first recovered datastore on the first IP, the next recovered datastore on the next IP, and so on, mounting the datastores the same way from each ESX host involved in the recover plan currently being executed.

Mount subnets

SAN Capabilities

The new SAN adapter for SRM is configured and works in exactly the same way as the existing adapters.  We’ve added some extra support for ensuring that the DR test environments created by the SAN adapter are completely thin provisioned on the NetApp side.  This means that whenever a SRM DR test is preformed the FlexVol volumes that are cloned have their volume space guarantees turned off, and the LUNs in those volumes have any reservations disabled.  These features ensure the DR testing environments created by SRM do not consume unnecessary space from the storage array maximizing the amount of SRM DR testing that can be performed.

NetApp Adapter Availability

VMware released SRM 4.0 on Monday, October 5.  The NetApp NAS adapter version 1.4 is currently available on the VMware SRM download site for customers who’ve purchased SRM from VMware.  The NAS adapter will also be available on the SRM Evaluation download page within a few days.

The NetApp SAN adapter version 1.4 is following closely behind and will also be available in the next few days.

I’ll be sure to update this post as soon as I know that the adapters are fully available. Once we get them available in the appropriate VMware locations we’ll also be making them available on the NetApp software download site.

We're also posting an version 1.2 update to our SRM on NetApp Storage technical report TR-3671 which we expect to be available by end of next week.  It will be available at the same link.



Hooray! We've all been waiting for this for so long!