Of VMware and NetApp

The organization that I work for uses Network Appliance as our storage vendor. Boy do we use it! To a tune of over 170 terabytes of storage! For our size organization I truly marvel at that number and wonder where it all goes.

That being said I truly believe Network Appliance to be the best storage vendor for SAN technology on the market. In one appliance you can get NAS, CIFS, iSCSI (they wrote the book on this protocol), Fiber, NFS, and a host of nifty tools and utilities you can work with. Also, their RAID protection protocol RAID-DP performs very well and offers advantages in terms of speed and reliability not found in other RAID typs.

So, what has caused me, as a VMware Engineer to love NetApp so much that I would sing its praises on a VMware blog? That can be answered in this way; Netapp allows me increased versatility and peace of mind in my VMware environment that I have been unable to find in any other SAN architecture.

One of the keys to this is a technology that NetApp has known as flexclone. With this technology I can take an immediate clone (or snapshot) of a system or LUN and then mount this flexclone on an existing system and it will be an exact point in time copy of the LUN that was cloned. This clone is merely comprised of pointers back to the original LUN and takes up virtually zero space starting out. This clone is also writeable and only the changes that are made take up space.

How can this help me you ask?

We have a scenario that requires us to have a DEV environment that needs rapid refreshes for its databases. Because our databases live on LUNs that are on the NetApp, we take advantage of this by creating flexclones of the database LUNs and mounting them on VMware servers which use iSCSI as the protocol to attach to the SAN. We have scripts that run on a schedule which creates these flexclones and mounts them on the servers in order to achieve the necessary refreshes. We do this with our DEV environments that require sporadic refreshes, TEST environments that require monthly refreshes, and BETA environments which use hourly refreshes in order to allow the developers to have access to current production data from our SQL environments. Also, should you want to make this flexclone permanent you can always split it from the parent LUN and the make it a standard LUN.

The great thing that we have found is that you can actually take a flexclone of a flexclone! This proves to be a wonderful concept when you want to test the changes you just made in the flexcloned DEV environment (cloned from production) but don’t want to risk making lasting changes at this stage or want the ability to revert back immediately in order to avoid lots of additional work. But that is just me “geeking out” at the moment.

Another area in which NetApp works very well with VMware is in the area of backup and recovery. In my environment I use RDM’s (raw disk maps) in order to mount SAN LUNs to the VM. Those RDM LUNs are where I place databases, programs, and other files that can change. I can then setup a snapshot cycle for those RDM’s for backup and recovery purposes. In the event of a problem that requires a restore, it usually takes me longer to type the restore command into the filer than it does for the filer to perform the restore! Its technology like this that allows me to sleep better at night AND serves the dual role of making me look REALLY cool when something bad happens.