Hello,
Yes, it is very much possible to migrate all the given SEP 11.x client directly to SEP 12.1 RU2.
Upgrade and Migration paths
Symantec Endpoint Protection 12.1.2 (RU2) can upgrade seamlessly over the following:
- Symantec Endpoint Protection 12.1.1101.401 (RU1 MP1)
- Symantec Endpoint Protection 12.1.1000.157 (RU1)
- Symantec Endpoint Protection 12.1.671.4971 (RTM)
- Symantec Endpoint Protection 11.x (can be upgraded to enterprise version only)
- Symantec Endpoint Protection Small Business Edition 12.0
Symantec Endpoint Protection 12.1.2 (RU2) can migrate installations of the following legacy Symantec products:
- Symantec AntiVirus Corporate Edition 10.x.
- Symantec Client Security 3.x
- Symantec AntiVirus for Mac (client only)
Note: A Small Business Edition product can be upgraded to the enterprise version, but the reverse is considered a downgrade and is not supported.
Check these Articles:
Supported upgrade and migration paths to Symantec Endpoint Protection 12.1.x
http://www.symantec.com/docs/TECH163514
Upgrading or migrating to Symantec Endpoint Protection 12.1.2 (RU2)
http://www.symantec.com/docs/TECH197426
Knowledgebase Articles for Symantec Endpoint Protection 12.1. RU2
https://www-secure.symantec.com/connect/articles/knowledgebase-articles-symantec-endpoint-protection-121-ru2
On a Kind note: I would recommend you to Migrate the SEPM / SEP clients to Latest version of Symantec Endpoint Protection 12.1 RU3
Latest Symantec Endpoint Protection Released - SEP 12.1.RU3
Best practices for upgrading to Symantec Endpoint Protection 12.1.3
Autoupgrade is the best practice to migrate all the clients.
Upgrading clients by using AutoUpgrade in Symantec Endpoint Protection
http://www.symantec.com/docs/HOWTO80780
VIDEO: https://www-secure.symantec.com/connect/videos/upgrade-clients-sep-121-using-auto-upgrade-feature
Hope that helps!!