Upgrading active-standby units to 10.2.4

Hi everyone,

We're planning to upgrade our customer's active-standby pair from 10.2.0 to 10.2.4 -HF5.

Systems are BIG-IP 1600 by the way.

Is it OK to upgrade the standby system only and have both units running diffrent software versions?, is it possible to sync configurations between them?

What we are planning to do is upgrade the standby one, do failover from the active one and leave the system running on the new release to make sure nothing gets broken...Once we are sure everything is fine, we'll upgrade the second unit.

Thanks in advance.

moog