Veeam, DDBoost Quota limits and reported free space

[DeadEyedJacks]

Found something interesting and quite useful today regarding using EMC Data Domain DDBoost storage units with Veeam as backup repositories.
Not seen this discussed or mentioned in the forum, helpcenter, knowledgebase or best practices.
(Let me know if I've missed it)

When no Data Domain storage quota is set Veeam sees the physical capacity and remaining free space of the whole Data Domain storage array.
i.e. 150TB capacity, 20TB free space.
This was beginning to cause us a headache at one location as Veeam looked at the remaining free space and refused to perform synthetic fulls for a job with 30TB of source data in it, despite this actually being easily achievable due to the massive dedupe space saving efficiencies of Data Domains.

What I found was if you set Data Domain quotas on the storage units, Veeam then sees the hard limit as the repositories storage capacity and reports free space based on this.
So with a hard limit of 250TB set, Veeam sees 120TB of free space and is happy to continue with synthetic fulls, although of course nothing has changed with the underlying physical capacity.

Thought this was a elegant solution and will look to set quotas on all our DDBoost storage units going forwards.

[foggy]

This is how DD reports its space utilization in cases where configured hard limit is higher than the actual storage unit capacity (which is in itself... a bit awkward?). Keep in mind that in case the actual space is over, the job will fail. And, probably even more important, if the job is not able to save some sensitive information (e.g. metadata) due to lack of space, the entire chain can become unusable.

[vDuck]

Hi

My customer using soft limit.
Veeam then sees the soft limit as the repositories storage capacity and reports free space based on this?

Sincerely,
S.T.

[foggy]

Yes, in general case Veeam B&R should see it as storage capacity and report free space based on it. However, if both limits are set, most likely the lowest is used.