Skip to main content

Hi Commvault experts,

 

are there any caveats when moving 3 DDB partitions (all have different volume/disk H:,I:,J:) from one Media Agent to the new one? Has to be a new Media Agent added to the Global Deduplication storage pool before the moving of the partitions? The point of moving is to move DDB partitions from the HDD disk to the SSD disk, while moving to the new Media Agent server.

And what about size of the new volume/disk for the DDB partitions? Is it just enough sum the amount of the Used Space on DDB Disks from all three DDB partitions?

 

There is a couple of articles from the documentation about ddb moving/sizing, but I would prefer hearing examples from real life situations/experience rather than encyclopedic axiom…- Tell me and I forget. Teach me and I remember. Involve me and I learn. rBenjamin Franklin]

 

https://documentation.commvault.com/v11/expert/hardware_specifications_for_deduplication_mode.html

 

https://documentation.commvault.com/11.16/deduplication_best_practices.html#creating-or-moving-deduplication-databases

 

https://documentation.commvault.com/v11/expert/moving_deduplication_database_to_another_mediaagent.html

 

https://documentation.commvault.com/v11/expert/moving_deduplication_database.html

Hello @drPhil 

 

As someone who worked in the Media Management support team for some time i have moved my fair share of DDB’s around. The GUI has very simple steps and its always worth noting that the DDB is completely recoverable from nothing so worst case scenario your backups done run for a few hours. So in my opinion it is mostly low risk. 

 

When it comes to where you can move it, the answer is anywhere that has the media agent software installed. 

 

When it comes to how large you need the disk to be, i always recommend to play for 5 years of growth. if you give it just enough space you will have to come back in a year and expand it. Sometimes that can be hard in the case of a physical machine and such. If you have Inf retention expect that DDB to grow substantial, if you have 30/60 days retention, it wont grow so much depending on the size of your environment growth. These are things to take into consideration.

 

The building block guide is very conservative and always over specs what you need but it does not mean it does not have its reason. Storage now days is very cheap when looking at the difference of a 1 or 2TB disk. I say just over spec but that is easy for me to say from a support perspective haha. 

 

Either way, just give it a crack. Worst case is you miss a night of backups.

 

Just don't do it on Friday   

-- Albert Williams while revering a change Saturday morning. 

 

Kind regards

Albert Williams


@Albert Williams  Thank you very much for your contribution.

Indeed, after performing the DDB partition move, I have to say that the move itself was quite smooth and without issues. However, keep in mind, if you're moving to a different Media Agent, the new Media Agent, the old Media Agent, and all related clients must have access to each other. In our case, we encountered problems because the Media Agents and some clients were in different VLANs, with a firewall in between.

According to the documentation (https://documentation.commvault.com/2023e/expert/hardware_specifications_for_deduplication_mode.html), the size of the DDB disk was set to 2TB – if this is acceptable, time will tell.

To sum up, I agree with the statement: when it comes to where you can move the DDB partition, the answer is anywhere that has the Media Agent software installed. Just keep in mind, there must be a connection between the devices.


Reply