upgrade from 10.0 to 10d

[Joyce_Warnacut]

Does this upgrade require reinstallation of all remote agents?

[steve_burkett]

No it's not required, but you should be planning on getting your remote agents upgraded at some stage to get the best performance out of your Backup Exec...

Taken from: Symantec Backup Exec 10d (10.1) for Windows Servers - Software Compatibility List (SCL)
http://seer.support.veritas.com/docs/278254.htm

Remote Agent for Windows Servers Compatibility

The Backup Exec 10d (10.1) Remote Agent for Windows and NetWare Servers is strongly recommended for use with Backup Exec 10d (10.1) for Windows Servers; the Backup Exec 10.0 Remote Agent is also compatible for the purpose of rolling upgrades with the exception of any caveats listed in the notes. The Backup Exec 9.x Remote Agent for Windows is not supported and not recommended for use with Backup Exec 10d for Windows Media Servers

[Ken_Putnam]

for the purpose of rolling upgrades

Depends on how you interpret this phrase. A v10d server will talk to a v10 RAWS, but the way I read it, only while you get around to installing the v10d Agent, On a permanent basis, you would be violating the licensing scheme