VM replication

[salmankhan99]

Hi All,

I hope someone can help\advise.

I want to protect a physical windows 2003 server machine from failure.

I have two Dell PowerEdge R710 servers with locally attached storage and I want to install VMWare ESXi\ESX on. I will then P2V the physical machine to one of the ESXi server.

If this ESXi server fails I want to be able to start the VM on the second ESXi.

My questions are:

- Can this be done without a SAN or shared storage?

- What VMWare product will I have to use so the second copy of the VM is up to date incase of failure?

- What VMWare licenses will I have to purchase?

Any help\advise is much appreciated.

[vmroyale]

Hello and welcome to the forums.

- Can this be done without a SAN or shared storage?

No.  Not without some sort of manual (time-consuming) work on your part.

- What VMWare product will I have to use so the second copy of the VM is up to date incase of failure?

VMware HA will restart VMs, in the event of a host failure.  This feature is available starting in Essentials Plus.

- What VMWare licenses will I have to purchase?

Check out the Edition Comparison chart.

Good Luck!

[salmankhan99]

Many thanks for the quick reply.

Can I not setup replication between the two ESXi servers, so any changes made to the VM are carried over to the second VM hosted on another ESXi server over the LAN?

[vmroyale · Accepted solution]

Yes.  VMware FT is a feature that keeps a 2nd VM up and running in constant sync.  You would need the Enterprise Edition to get the FT feature.  There is always the option of using 3rd-party clustering or replication solutions as well.

[EdWilts]

salmankhan99 wrote:

Can I not setup replication between the two ESXi servers, so any changes made to the VM are carried over to the second VM hosted on another ESXi server over the LAN?

This feature is available with the Virtual Storage Appliance that was announced for vSphere 5.0.  There are 3rd party storage appliances that do this kind of stuff too (LeftHand from HP is one of them).

Your best bet, however, would be shared storage - that eliminates all of the overhead and failure points of replicating the local storage between the 2 servers, and may possibly be cheaper since you're only buying the storage once.  Dell has some low-cost storage options as do other vendors like HP (with something like an MSA2000).

Depending on how this specific guest works and how current your data needs to be, there are lots of other options like cloning the OS disk to the other host and then doing regular synchronizes of the volatile data store.  Perhaps something as simple as a backup/restore might fill your needs if the recovery doesn't need to be instant.

[salmankhan99]

With shared storage. If the storage device fails will we not lose the VM? single point of failure?

Cheers

[EdWilts]

With shared storage. If the storage device fails will we not lose the VM? single point of failure?

Absolutely. Your shared storage must have redundancy built-in.  Typically this is done with redundant controllers with RAID storage.  Your hosts should have multiple paths to the storage.

If you want high availability, you must realize that there is a price to be paid.  The higher the availability requirement, the higher the price, and it's not linear.

[depping]

salmankhan99 wrote:

With shared storage. If the storage device fails will we not lose the VM? single point of failure?

Cheers

For that you will need to protect your Storage device on a different layer through replication... FT or HA will not do this for you.

Duncan

Yellow-Bricks.com

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