Start a Conversation

This post is more than 5 years old


Go to Solution


November 14th, 2013 07:00

Avamar sizing query

If 4TB data is to be backed up across many clients at one location. initial Backup window is 80 Hrs.

How many minimum 2 TB nodes are required? and how ?

5 Practitioner


274.2K Posts

November 19th, 2013 06:00

The second formula you listed is from the client's perspective. It shows how much the client is able to process per hour AFTER the initial backup. This is usually the number you want to look at since the client is usually what limits the backup speed.

The exception is when there are a large number of clients. At this point the server's connection limit becomes a factor since not all clients can run simultaneously.

The first formula you listed is good when you have a large number of clients, such as in a DTLT environment. (Although I think it should be "No of backups per connection per hour", not per storage node. Each storage node has 27 connections) In order to use the first formula, you need to already have an estimate of how fast a backup from a typical client can complete. Note that this formula doesn't take into account how much data, just how long the backup takes. For example, if it takes the average client 5 minutes to complete a backup of their data, that would be 20 backups per connection per hour.

So, to summarize, you can use the second formula to find out how long it would take your average client to perform a backup. Then, use the first formula to see how many backups per hour could be performed across the whole environment with X amount of nodes.

You'd need to know the actual number of clients and their amounts of data to use these formulas, but as Dheeraj stated, a single node should do it. 26 connections (remember, 1 connection per server is always reserved for restores) that do an initial backup at 10 GB/hr will complete in about 15 hours. Backups after that will complete faster. (This assumes that each client has a similar amount of data)

633 Posts

November 18th, 2013 10:00

It would be helpful if you could explain how you currently understand the question. Are you using a particular formula?

November 18th, 2013 11:00

Well i was going through the Avamar study material . There are 2 formulas that made sense, i am just unable to correlate them for this query

--> No of nodes * No of backups per storage node per hour * 27 = No of backups per hour

--> 1 hour for every 1 million files to backup in file server &  1 hour for every 100 GB of data in DB server.

Feel free to correct or update incase i am missing on something.

3 Posts

November 18th, 2013 21:00

In my openion it should be a pair of 3,9 TB single node because EMC
recommends replication if you are using sungle node for backup, and you have
enough time frame for backup because during initial backups, the client can
typically process data at approximately 10 GB/hour

No Events found!