Hello,
BE 12.5 does not support Window 2008 R2 as Media server. Also BE 12,5 as media server and Remote agent of BE 2010 will not work together.
You can have BE 12.5 installed on other supported OS (Win 2008, 2003,2000) and BE 12.5 Remote agent working on Windows 2008 R2 server and it is partially supported which means it is supported only for backups of (
(File System, System State, Shadow Copy Components Only). Any backups of applications like Exchange,SQL, etc are not supported.
For more information on this you can refer to
http://support.veritas.com/docs/335868
I suggest you can install Backup Exec 2010 R2 on your Windows 2008 R2 machine and also install the remote agent of BE 2010 R2 on other servers to work fine. You can also test that in the Evaluation period of 60 days. Visit
www.backupexec.com to download BE 2010 R2.