Storage size requirements for backups

[blckblt]

I have 35 Vms to backup and I trying to plan out the storage needed for the backup destination. If I have a 300 GB VM do I need to plan for 300 GB on the backup destination? All of my VMs are Windows 2003 R2 or 2008 R2.

Thanks.

Tyler

[alexfeig1]

Normally - no. Because Veeam deduplicates and compresses, it depends entirely on the kind of data you are backing up.

If you were backing up a server full of zip files, you would probably need close to 300GB.

If you were backing up a server full of text files with the letter "A" repeated over and over again, you would probably need less than 10GB (Just an example).

There's no clear cut formula.

I back up about 11TB worth of VM's and it uses about 5TB for 14 days of retention.

[Vitaliy S.]

Tyler,

Alex is correct, everything depends on the dedupe/compression VM ratios you will have (which is hard to predict based just on OS types).

Moreover the storage size calculation relies upon on the backup mode you've chosen (Forward or Reversed Incremental) and the retention policy you've specified for the jobs. And don't forget about VM daily changes and desired job schedule.

You may want to have a look at this formula which should help you to predict storage usage for Reversed Incremental backup mode:
http://www.veeam.com/forums/viewtopic.p ... 498#p14246

Besides, you can refer to a Check Space button, that can be found on a Backup Destination step of the Job creation wizard. That should give you an approximate size requirement for your target storage.

Hope it helps!

[dogzilla]

[merged with existing discussion]

I'm trying to work out my storage requirements before rolling out Veeam.

Has anyone got any real world figures in terms of disk sizing?

If for example I've got a VM with 50GB disk and 30GB in use, I take it only 30GB will be backed up. What about subsequent backups? Does it re-image the whole VM every time? Or does it do delta type backups?

[Vitaliy S.]

All subsequent job runs will be incremental. There are two types of backup modes, please have a look at this post for more information:
>>> READ THIS FIRST : [FAQ] FREQUENTLY ASKED QUESTIONS <<<

[pbpb]

[merged into existing discussion]

Hi

We are looking into buying Veeam Backup for our Vmware enviroment.
Is there an calculator for hardware? I mean how much diskspace and wich type of server should we use.
I understand this is impossible to get an specific value but we need a hint.

We are looking into backup for 250 Virtual Machines. 30 TB total disksize (probably less because of deduplication, all windows 2008 machines)
General backupschedule: Full backup every week and then incremental every day.

Thanks

[pbpb]

Found this:
Backup size = C * (F*Data + R*D*Data)
Replica size = Data + C*R*D*Data

Could this be a good calculation:

Backup size = 50% * (1*30 + 14*10%*30) = 36 TB
Am i thinking correctly?

What is replica size?

[Vitaliy S.]

Replica is the size of your replicated VM in case you're going to use replication jobs with rollbacks.

[GabesVirtualWorld]

[merged into existing discussion]

Hi

So now I'm using Veeam in my customer's environment for a number of weeks and getting a good feeling of change ratio's and compression ratio's. But, we're still in test phase and writing to one single disk of 2TB. Yes, I'm sorry about that too.

To apply for a new NAS to store the backups on, I need to do some math to figure out how much capacity I would be needing and was wondering if this is available already.

I would like to enter parameters like:
RAW 1420GB, Full backup 540GB, compression / dedupe ration 40%, daily incrementals 10% of full.

Now how much storage would I need when I want 30 daily backups, 4 weekly per month, 1 monthly, 1 yearly and save all monthly backups for 7 yrs.

Anyone got such a nice tool for me?

Gabrie

[Alexey D.]

Gabrie, you can refer to the formulas in the post above. Here is the legend to use:

Data = sum of processed VMs size (actually used, not provisioned)
C = average compression/dedupe ratio (depends on too many factors, compression and dedupe can be very high, but we use 50% - worst case)
F = number of full backups in retention policy (1, unless backup mode with periodic fulls is used)
R = number of rollbacks (or increments) according to retention policy (14 by default)
D = average amount of VM disk changes between cycles in percent (we use 10% right now, but will change it to 5% in v5 based on feedback... reportedly for most VMs it is just 1-2%, but active Exchange and SQL can be up to 10-20% due to transaction logs activity - so 5% seems to be good average)