Recommendation for retention on copy job

[jamcool]

We have a daily backup job that we keep 14 backups and do synthetic full backups on Saturday. We also do a daily copy job of the backup job to another repository in another datacenter.

Our customer wants to be able to restore back 90 days but is fine if only have weekly backups in the copy to restore from. They mainly restore file(s). We agreed keeping just 13 weekly backups would be sufficient. So I set the copy job to keep 20 restore points and 13 weekly (under keep the following restore points as full backups). The reason I set it to 20 was so that would have current incremental backups for that week once we get to having 13 weekly backups.

It has now been 14 days and I have the initial backup that is full and 13 incremental backups.

So my two questions are:

1. When the copy job gets to 20 restore points will it start doing more than 1 full weekly full backup?
2. Would I be better to not do 13 weekly full and set it keep 90 restore points to save disk space? The full backup is expected to be 12 TB but the incremental backups are about 100 GB. If I keep 13 weekly full backups that is 156 TB of space. If set to 90 restore points with just one full backup and 89 incremental backups, then I am about 22 TB. I know the risk if the full backup or incremental backup is corrupt you have nothing or limited restore. Thoughts? Suggestions?

[Mildur]

The weekly gfs restore points will get created as soon the first 20 incremental backups are created.
After that, veeam will synthesize the weekly gfs from the 20 restore point chain.
Veeam will never create the weekly restore point for a specific saturday on this specific saturday.
You have to wait until the 20 copy restore points are created.

If you use reFS as a repo file system, your 13 vbk doesn‘t need 156TB, they need only around 15-16TB for 13 vbks.

[jamcool]

Thank you for the information. We been using REFS since day one so can get quick synthetic "full" backups. Just has to move pointers around instead of actual data compared to NTFS. Also REFS deals better with big files.

I will try to reply back in a few months with how it goes and if it turned out only needed 15-16 TB with all those weekly backups or if we do something different.

[foggy]

1. When the copy job gets to 20 restore points will it start doing more than 1 full weekly full backup?

It will start merging the oldest incremental into the existing full backup, there will be no new full backups in the regular part of the chain, only weekly ones.