Avamar experiences

[jb12345]

Does anyone have any positive or negative experiences with Avamar?

We are looking at installing Avamar to backup our VMs to a Data Domain.  We have vCenter 4.1, ESX 4.0 & 4.1 and about 200 VMs that we will be backing up.  Among these VMS we have Exchange, SharePoint, SQL and Oracle along with the 'normal' mix of applications.

Thanks for your input.

[jb12345]

No replies.

[mcowger]

The avamar vmware backup suite is somewhat new, so you may not see many people using it yet.  Might be better to ask your EMC TC for a reference call.

--M

(disclosure - I work for EMC)

[tony_mcphail]

Have just deployed Avamar 5.0 to help with the transition from tape to disk for backups. Full image backups of VM guest works well. Have only recovered an image to a new Guest but have done a full production server used to host our payroll system which included MS SQL. Worked out well.

Need to be aware of the issues with snapshot files being left behind, and in our case it is a bit slow. 2 hr to backup / restore a 200 gb guest.

[jb12345]

FYI - we are just finishing up an Avamar POC.  At this point I doubt it will be our solution.  In order to fit all of the backups in our time window (about 400 VMs) we needed to install 20 Avamar proxies.  While the proxies are easy to roll out I don't need to add even more appliances to my configuration.

[DenisJannot]

To backup 400 VMs, you will need 6-8 proxies.

One proxy is only 1vCpu, 1 GB of RAM and 4 GB of disk space, so you will need 8 GB of RAM to backup your 400 VMs !

That's one of the biggest advantage of Avamar, it scales using proxies.

We have customers backing up more that 2000 VMs with one Avamar server.

[rash127]

Avamar proxy systems are HotAdd hosts. They have all the current limits and issues present in HotAdd (See VDDK release notes for details).

The other problem is that Avamar proxies support just one stream at a time. This may or may not be a challenge based on your data change rate in VMs. If things are not changing much, you are fine as Avamar proxies are only sending the changed data.

Another issue is that you need to maintain seperate proxy hosts for Windows and Linux VMs. All these comments are based in Avamar 6.

Warm regards,

Rasheed

Disclaimer: I work for Symantec. Comments are my own. 

[DenisJannot]

Hi Rasheed,

I answered you about the HotAdd limitation in the other discussion

Here is an extract of the Virtual Disk API Programming guide :

For LAN transport, virtual disks cannot be larger than 1TB each. As its name implies, this transport mode is not LAN-free, unlike SAN and HotAdd transport (http://pubs.vmware.com/vsphere-50/index.jsp?topic=/com.vmware.vddk.pg.doc_50/vddkPreface.html)

But,the block size chosen for the VMFS that holds the proxy is also important.

It must be 8MB to allow backing up a 2 TB virtual disk.

The proxy can do only one sessions at a time and the duration of on backup will be around 1 to 10 minutes depending of the size of the VM and the modifications since the last backup.

A proxy is using only 1 GB of RAM. That's easier to predict the number of proxies you need when you backup one VM at a time with a proxy using 1 GB of RAM, than when you backup 4 VMs at a time with a proxy using 4 GB of RAM, and at the end you are using the same amount of ressources in your VMWare environment.

Yes, you need seperate proxies for Windows and Linux backups in 6.0.

Again, it's only 1 GB of RAM each. And this limitation won't exist anymore in the next release.

Best regards,

Denis

[DenisJannot]

Hi,

With Change Block Tracking enabled, a backup of a VM will be done in less than 5 minutes in 99% of the cases.

To use Change Block Tracking, you need to have your VMs in VM Hardware 7 (this is the VM Hardware available since VMWare vSphere 4).

And if you upgarde to Avamar 6.0 (which is available since several months), you will be able to recover a VM in the same time because it leverages CBT also for recovery (if your VM exists).

Best regards,

Denis

[DenisJannot]

Hi,

Avamar backups VM to Data Domain is working really well.

I have posted a record on my blog (http://www.recorditblog.com/?p=25) to demonstrate that.

And as Avamar licensing allows you to deploy as many agent as you need, you will be able to do hot backups of all your applications.

Best regards,

Denis