Hi,
Total how many clients do you have in the network?
If you have limited number of clients then I would suggest to go with fresh install.
If clients count is high the you can go with any of the following option
There are two methods to move Symantec Endpoint Protection Manager (SEPM) from one machine to another:
Method 1: if the SEPM server keeps the same IP and host name, you can refer to "Best Practices for Disaster Recovery with the Symantec Endpoint Protection Manager"
http://www.symantec.com/business/support/index?pag....
Method 2: if the new SEPM server has a different IP and host name, there are two alternatives:
1. Use replication to install a new SEPM and keep the policy the same with old SEPM. See "How to move Symantec Endpoint Protection Manager from one machine to another"
http://www.symantec.com/business/support/index?page=content&id=TECH104389
2. Install a new SEPM, then use the Sylink file to establish communication between the new SEPM and the existing SEP client through sylink replacer tool.
Note : Sylink replacer tool is most commonly used option because it's easy to use.
Please go through following thread for more details:
https://www-secure.symantec.com/connect/forums/migration-clients-other-server-sepm#comment-5229601
Link for more information :
http://www.symantec.com/business/support/index?pag...
Q. Are there any known issues about such an upgrade or move I should be aware of before I start?
--> To upgrade to the latest vesion of SEP you will have to upgrade to SEP 12.1 RU1 then SEP 12.1 RU1 MP1
Probably SEP 12.1 RU2 will be released on 6th of Nov'12. After this release you can directly upgrade to SEP 12.1 RU2. It will save you time & efforts.