Case #01762544 [ref:_00D30RWR._50032zpxbb:ref]
I'm posting this issue because veeam support has urged me to do it, so they can overview the impact this issue is having in their user's community. It's important that all of you that is facing this same problem take the time to update this ticket in any way, so Veeam can assign to this question a high or low priority.
The problem is that when the "Use Encryption" option is enabled in the "Options" tab of the properties of a Tape Pool, the performance of the jobs that use this pool becomes a fraction of the speed obtained without this option selected. In my case, using LTO3 drives in a MSL6030 from HP, the normal speed of a backup job using an unencrypted pool is 80MB, that is the full speed of a LTO3 drive, while the speed obtained using this same pool but activating the option indicated before, the speed slows down to 34MB.
The answer from Veeam is that this issue is considered to be by design, just because the encryption process is made of only one thread, and this is a slow mechanism.
So, they are collecting statistical information to face this issue with the more adequate priority.
If any of you is facing this same issue, this is the correct place and moment to leave a reply.
In my case this issue is forcing me to make tape backups in different days because of lack of time, and this is very problematic.