Migrating from ISE 1.3 to 2.1 and new hardware

[matthen]

My customer sent me the following question, is it possible to keep the cluster fully intact when restoring from a backup?:

"I have the 2.1 hardware in an existing cluster with the same name and IP addresses as the 1.3 cluster.  I also imported the 2.1 self-signed certs into the trusted store of the 1.3 cluster so the new nodes will already trust one another.  When I restore the 1.3 backup to the 2.1 cluster it removes the admin node I’m performing the restore on from the cluster and turns it into a standalone node.  I realize at this point I can simply start joining the remaining nodes to the cluster but this will take a long time.  Is there a way I can restore the 1.3 backup to the 2.1 cluster while keeping the 2.1 cluster fully intact?  Would including the ADE-OS data allow this to happen?"

[paul · Accepted solution]

If you do the CLI upgrade path to 2.1 you keep the deployment intact, i.e. you don't have to put it back together as the upgrade process will do it for you.  I would never do an upgrade using the CLI upgrade path.  You are much better doing the rebuild and restore method and putting the deployment back together yourself.  Having done probably 50+ of these I don't agree with the statement "It takes a long time" to add nodes to a deployment.   It is not different than the upgrade script doing it.  Should take roughly the same amount of time if you know what you are doing.