I've done this pretty easily. The first thing you need to do is isolate a window for no changes. This is very important if you are upgrading to the newer hardware because its running 10.1 or later. F5 has taken away the ability to sync between different versions of 10.x series of code levels. The older 9.x series you could sync the data over. Now once you have picked a window generate a ucs backup of both boxes. You can import the ucs into the newer boxes since it will modify the configurations to match 10.1 or whatever code level you are using. Now comes the fun part. The night of the change take the standby out of the network and remove all cables. If you are running in an active/standby configuration plugin the db9 sync cable into the new standby unit and power it up. Once its fully booted connect your network cables and validate you can reach everything in your network. Also check the VIP/pool's/node status and make sure both boxes match on whats up/down. Now you can failover and do the same steps with the current standby unit. Also I would recommend upgrading to 10.2 if you get time. There are quite a few known issues with 10.0.x
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