Zerto vs array based snapshots with replication

I want to take a moment and discuss a few feature sets from some of the popular storage vendors on the market today and where their replication technology may overlap with Zerto. I have been doing some shopping lately for a storage array. I’m not talking about the big boys at EMC, NetApp, IBM or HP. I’m talking about the guys growing in popularity like Solidfire, Nimble StorageTintri and Tegile. Violin and Pure Storage are all flash arrays, these are a different animal but provide the same type of replication and snaps. When you are looking at these storage array vendors in the enterprise or cloud space (more often than not) you will find overlapping features with some tools you may own. In the Zerto documentation it states that replication and snapshot management requires IT overhead when using the built storage array features. How true is this?  Nimble Storage is the only one on my list that has a plugin for SRM today, but we are going to talk about the built in features to the array and not VMware SRM. Remember, all of these require more than one like array if you want to take advantage of replication. And also, replications and snapshots do not always give you an orchestrated failover and failback architecture. Most of these will include features with the array and others may charge to turn on a feature. Let me first say that all of these storage arrays are fantastic. They are very forward thinking and each have a great place in the enterprise and cloud space.

Tintri logo

Tintri is built on a application aware storage architecture. The array is purpose built for virtualization. Tintri has three main features. Clone, snapshot and protect. The cloning feature is pretty nice because it allows you to clone form an existing, past or present snapshot (Tintri storage snapshot) to another Tintri array or to the same one.

The array can give you a view from the vCenter web client of all the snapshots from Tintri.

Tintri snapshots







You can setup a schedule to “protect” the VM with a snap and make it crash consistent. You can keep this local to the array or remote to another Tintri array.

Tintri protect






If you create the snap to another array you can view the bytes remaining to replicate and the throughput.

Tintri replication throughput

Tintri replication status






All of these features are great, but what are you going to do with that replicated copy once it is on the other side? There is no orchestrated way of bringing it online or doing reverse protection once you have it up.  I’m sure there is a way to work with the Powershell cmdlets to get something working, but that would require many man hours. Zerto does this for you. To replicate VMs from one location to another, two separately license product must be purchased. Tintri Global Center and ReplicateVM. In my use case, I would use something like this to replicate VMs to another datacenter so that I could import them in to vCloud catalogs or work with a production VM offline. The cloning feature would be great for creating VDI sessions as well.


Tegile logo

I had a hard time finding any technical documentation on the Tegile web site. Most of what I found was marketing material. You will find plenty of whitepapers, solution briefs and customer stories. But there is not much on how replication functions. What I did find was a lot of product demos on YouTube. One goes through the demo of dedupe, compression and recovery. On the recovery piece, you can see that it is still a manual process. Nothing automated like Zerto provides. Tegile did partner with Voonami to provide offsite replication with its array.

Tegile does has a file level protocol that is SMB 3.0, which can be used as a Zerto backup target. They have partnered with Veeam to provide the backup solution. Veeam does have a great set of tools.




Solidfire logo

Only SolidFire delivers native snapshot-based backup and restore functionality usable with any object store or device that has an S3 or SWIFT compatible API. SolidFire now offers the SF2405 and the SF4805  with enhancements to SolidFire’s real-time replication offering with a storage replication adapter (SRA) for integration with Site Recovery Manager (SRM).

The real time replication built in to the array is not a full DR solution. Investments must be made into SRM and you must have like arrays at the sources and destination. On the VMware side, this would require a 25 pack of licenses for SRM or vCloud suite licensing on all of your hosts.


Nimble logo


I think Nimble has the most comprehensive tools when it comes to replication. Nimble has a post on Nimble OS 2.0 that does a walk through of how to configure replication. This covers only the array based replication. With the backup solution, Nimble has included a set of tools for backup and recovery. They have also partnered with CommVault Simpana to provide a more comprehensive back and recovery process. You will need to register on the Nimble website to get all the details with a best practice document. What it comes down to is that the CommVault solution is still a backup process. It is not a real time replication product like Zerto. This tool relies on array based snapshots and is not at the kernel level like Zerto’s VRA. The recommended snapshot duration from CommVault is 15 minutes. A lot like vSphere replication out of the box. Although Nimble can handle snapshots up to a minute. The recovery process is still manual.

Nimble also integrates with VMware SRM. This is the DR method listed for the array in a VMware environment. They have also included a webinar demo of the array with SRM.


To sum it up, I think that each one of these storage vendors has great potential to replace some virtualization backup solutions but not replace an orchestrated BC/DR solution like Zerto. When you look at one of these storage vendors, think about what your current backup solution does and how it compares to what the array provides. Zerto does provide an offsite backup solution with the product, but it does not provide dedupe or compression at the source today like Avamar. However, you do get dedup when you use a backup target like Windows 2012 R2 and turn on those features or with a storage array that offers this. The target must be an SMB share. Or you can just use a TNT drive and backup to the cloud. What I do like about the Zerto offsite backup product is that it does the backup against the replicated VM at the target site. This reduces resource overhead at the source site. You would not need dedup at the source since the backup does not happen there.

Think of it this way, if you get fed up with your current storage vendor and you want to move to something else, how would you go about reconfiguring an BC/DR plan? If you just use Zerto you will not have to worry about losing any features because the product is storage agnostic! If you made investments in to SRM you might find yourself locked in to sticking with the same storage vendor. The storage array vendors treat SRM like a car dealer does the 3rd party warranties they sell when you buy a new car, they may not tell you about another vehicle warranty company if it is not a built in feature of the product line they are selling, it is up to you to know there are other options out there. It is in the storage vendors best interest to get you tied in with SRM so that you will either buy more than one or stick with the array vendor down the road to depend on the array replication features. If a storage vendor requires you to pay an additional license for a VM protection feature, it may be in your best interest to just stick with one solution like Zerto to reduce overhead. Some times technology overlap is unavoidable, but look to Zerto as the BC/DR solution for your virtualization environment.

I will be adding more vendors to this list as I have time.

One thought on “Zerto vs array based snapshots with replication

  1. Would you still recommend Zerto today? The new gen, as well as some of the older. storage array vendors are adding more and more features both in the hardware and in management software. I don’t think the choices are as simple but being storage agnostic is still huge.

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