Please help to understand media agent with deduplication. Unable to understand Commvault documentation link

  • 14 September 2021
  • 8 replies

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Please help me to understand commvault media agent with deduplication



8 replies

Userlevel 7
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Hi @Mansoor - happy to help, but its a big topic so you may need to be a bit more specific on what you need to know or understand. Is this about deployment, how it works, how to configure etc?

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@Damian Andre Yes, i need to configure media agent with DDB in cloud and prepare hardware configuration for MA. 

i need to understand media agent Deduplication concept .

  • Currently planning to go with 3 Large size MA with DDB
  • what is the SSD hard disk size for MA with DDB?
  • How many clients backup it can hold ?
  • what will be Network configuration of MA?
Userlevel 7
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@Mansoor , I have a few docs that will help.

this guide covers every concept regarding deduplication and is a great place to start:

This guide will describe how to size your MAs depending on your use case:

Let me know if you have any questions this doesn’t cover.

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@Mike Struening Hi Mike, what is the difference between “Back-end Size for Disk Storage” and “Disk layout?”

Also Brief on Parallel Data Stream Transfers

Hardware Specifications for Deduplication Mode (

Userlevel 5
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Hi @Mansoor ,

Back End for Disk Storage tells you what size (Back-end) the Media Agent(s) will be Capable of, depending on the configuration. - Example below:
3x Large MA’s with 1DDB = 450TiB Back-end Storage
3x Large MA with 2 DDB Disks = 900TiB Back-end Storage


For Disk Layout, This tells you the config required for the MA: 

For each Large MA you need 400GB OS Disk, 1.2TB SSD DDB Disk and a 1TB SSD Index Disk:


Best Regards,


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@MichaelCapon Please confirm whether my understand is correct or not.

Back end storage size = Azure blob storage capacity or HP store once Storage capacity

3x Large MA’s with 1DDB = 450TiB Back-end Storage -- It means this configuration can manage only 450TiB Azure blob storage?

Userlevel 5
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Hi @Mansoor ,

Back-end storage size (disk) would be the Capacity for the Disk Based Library, yes.

Are you deploying on-prem or in cloud (Azure) or both? - For Azure we have a Cloud Architecture Guide here:

Since Cloud Storage uses a Higher Deduplication Block Size (512kb) the calculations here are different, for a Cloud MA:


Best Regards,


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@MichaelCapon Below are my details:

Backup server  : On premise

MA : Azure cloud

Backup types : Oracle DB and Oracle Archive backups:

Backup end Storage : Azure blob storage(hot and cool)

i need to deploy Media agents to manage 500 to 700TB cloud work loads,

what can be best media agent sizing. please provide your input

Initially i am starting with 3 Large Media agents with 8Vcpu and 64 GB RAM, 1 TB SSD Index cache & 1 TB DDB Storage.