Increasing restore points / full backups

[r.mckeon]

This is my scenario: 2 VMware 5.0 ESX hosts, with approximately 14 VMs being backed up. They are all backed up daily using Reverse Incremental backups. We keep 8 restore points and take an active full backup every Saturday. This means that for each VM we have 1 full backup, 7 reverse increments and another "full" backup which is the most recent reverse backup file. The vbm/vbr/vbk files are backed up to an iSCSI repository on a physical backup server with Veeam B&R 6.5.

This scenario means we can restore data back by a week + 1 day. The client now wants us to increase the time we can restore from to be 1 month. I know I can simply increase the restore points to be 30 or 31 instead of 8, but I have a few questions:

• 1. If I simply increase the amount of restore points, what effect will this have on the already existing Veeam backup files (vbks/vbrs etc)?
  2. Currently we take an active full backup per VM every week. I don't want to end up with 4 full backups, I just want the 1 full backup, the "full" backup which is the most recent reverse incremental file and obviously the 29 or so reverse increments (I don't know if I'm being understood). So if I increase the restore points to a month, and leave the weekly active full backup as it is, in the second/third/forth week of backup runs will the active full backup be overwritten with the new one, or will it create a new file every time?

Thanks!

[dellock6]

1. existing restore points will be kept until they reach the new rentention period, afterwards they will be removed
2. honestly I don't see at all the need to create a weekly active full if you are using reversed incremental. The only result here is that you are consuming much more I/O to create the increments, without saving space thanks to the single full capabilities of the reversed incremental. I would simply change the retention to the new one, and set it monthly. Once every 2-3 months is more than enough if you simply want to reset the chain.
3. if I was you, I would take a look at the new Forward incremental-forever method, same space consumption of reversed incremental with a lower I/O profile

[r.mckeon]

3. if I was you, I would take a look at the new Forward incremental-forever method, same space consumption of reversed incremental with a lower I/O profile

Thanks for your feedback. The main reason we use reverse incremental is that since the latest backup is always full, we will save a lot of time in the case of restoring an entire VM, where-as with a forward incremental mode (forever or not), Veeam will need to consolidate all the forward increments, which as far as I know will take a long time. I might be mistaken though...

[foggy]

You're not mistaken, there is indeed an impact in case of extremely long chain. Though not due to consolidation but due to how metadata is stored (in each increment separately). However, keep full backup fragmentation in case of reverse mode in mind too, as it also affects the time required to get necessary data from the disk.

[dellock6]

There's no consolidation, blocks are directly read from respective increments, only metadata pointing to different backup files are read but they are small and quick to be read. There could be a difference in performances on long chains, but not surely on a 7 days chain...

[r.mckeon]

Basically I was thinking of just increasing the restore points to 30, and making the active full backups monthly.

So to understand clearly, with reverse incremental, can it be a forever-incremental backup? Seeing as its creating a new full backup every time it backs up. In which case I wouldn't need the active full backups at all.

[veremin]

So to understand clearly, with reverse incremental, can it be a forever-incremental backup?

With reversed incremental mode there is still need to perform active full backup on regular basis. Once a month or so.

Forward incremental forever backup, as it stands from its name, can run without active full backups, though. Also, it works essentially the same as reversed incremental does, but at the cost of less load put on target storage.

Thanks.

[dellock6]

Reversed is indeed a forever incremental. The "new" full that appears because the incremental is injected into the same full backup every day, but the file is always the same, it's not re-written from scratch daily. You can understand how the different backup modes work here, there are some nice animations:
http://www.veeam.com/kb1799
and then follow the link to the different backup modes.

Luca.