Backing up to tape preserving VM restore and vfi

[dazza007]

I am looking at changing our backups to write to our tape system. We are going to write to disk daily backups and monthly export a full working backup to tape.
Can you advice and correct me if I am wrong in the following

I understand that backing up to tape requires forward incrementals to minimise errors for VM restore
By using synthetic full/active periodical backups allows a VM restore when using forward incrementals
Activating Transforms allow space to be preserved

I want to setup daily backup with weekly functional full vm restore points once a week
From this I need to write a monthly backup to tape

Therefore my plan is to use forward incrementals, to use either synthetic full/active full backup once a week so I have a month (4 points) that VMs can be fully restored. One of the full/synthetic backups will be written to tape at the end of each month. What are the disadvantages of using Transforms?

As you can see I have read lots and it is confusing me !!!

Thanks ALOT in advance

[foggy]

Darren, thanks for reading prior to posting. A few corrections below:

I understand that backing up to tape requires forward incrementals to minimise errors for VM restore

Actually, backup mode does not play huge role here, both forward and reverse incrementals can be equally used in conjunction with tape backups. Not sure what kind of errors are you referring to.

By using synthetic full/active periodical backups allows a VM restore when using forward incrementals

Yes, it is recommended to perform periodic fulls to avoid extremely long backup chains. However, this is not a hard requirement for full VM restore, VMs can be restored from any incremental restore point, provided that entire backup chain is available and not broken.

Activating Transforms allow space to be preserved

That's correct.

What are the disadvantages of using Transforms?

I cannot see any disadvantages except some storage I/O overhead.

[veremin]

One of the full/synthetic backups will be written to tape at the end of each month.

For now, If you want to copy only the latest full backup to tape mediums, you have to utilize file to tape job in conjunction with hard links. Thanks.