Backup Plan!

Hi all,

I am new to backup world and new to backup exec 2012 as well. Therefore i hope that i can get usefull advices from all of you.

Note : I am having 3 ESXi host + vcenter + 1 backup exec 2012 on physical sever.

Backup Retention:

+ 1 Month backup retention
+ duplicate full backup at the end of each month to tape for MONTHLY BACKUP ( keep for 1 year)

Can you advise on my backup schedule below ?

+ Backup Disk to Disk to Disk ( Disk - to - DAS - to - NAS ) everyday. Then duplicate full backup at the end of each Monthy to Tape LT05

License 

I am having license of Backup exec 2012 + 2 agent for app/database + 1 agent for Vmware and my environment is 100% virtuliazation. My questions are :

1. should i just buy 1 deduplication agent for my backup exec 2012 server to reduce space in DAS(SAS disk) and NAS (SATA disk) storage ?
2. Should i buy 1 Vmware agent for 1 ESXi host ? for example i have 3 ESXi host + 1 vcenter, should i buy 3 Vmware agent ?

Thank you all very much.