Try #2, sorry. My original reply got canned for overquoting, so let me see if this gets through to the group.  Pete HYPERLINK "http://www.oracle.com/"; \nOracle Pete Sharman Principal Product Manager Enterprise Manager Product Suite 33 Benson Crescent CALWELL ACT 2905 AUSTRALIA Phone: HYPERLINK "tel:+61262924095"+61262924095 | | Fax: HYPERLINK "fax:+61262925183"+61262925183 | | Mobile: HYPERLINK "tel:+61404005744"+61404005744   _____  "Controlling developers is like herding cats." Kevin Loney, Oracle DBA Handbook  "Oh no, it's not, it's much harder than that!" Bruce Pihlamae, long term Oracle DBA  _____   From: Peter Sharman Sent: Wednesday, 19 October 2011 10:40 AM To: Upendra N Cc: development@xxxxxxxxxxxxxxxxx; Oracle-L Subject: Re: Oracle Grid... ahem Cloud Control 12c  Sorry, at the Australian 12c launch, so I just saw this.  If you were doing a one system upgrade, you will be upgrading your existing repository, so that keeps everything you had.  If you are doing a two system upgrade, you clone the existing repository, leaving the old version with pre-12c agents pointing to it. You can then gradually install 12c agents pointing to the new repository.  That means you have both running, pre-12c and 12c, each with its own agents. As you move the pre-12c agents, you can sync the history as part of the move to the 12c repository. Pete On 18/10/2011, at 10:34 PM, Upendra N <HYPERLINK "mailto:nupendra@xxxxxxxxxxx"nupendra@xxxxxxxxxxx> wrote: With the EM upgrade, when we re-register the targets do we loose the history of the metrics gathered? Is there a way to preserve the performance metrics history? -Upendra -- //www.freelists.org/webpage/oracle-l