best option to migrate config from 3600 to i2600

Platform migrations are never easy. The master key is used to encrypt and decrypt the various passwords in the files. The easiest way to accomplish this would be to replace the encrypted passwords and passphrases with the plain text. You should be able to load the configuration

tmsh load sys config partitions all

Once the configuration is loaded, and assuming that you didn't get any errors, you will want to check the last few lines of the ltm file to make sure:

tail /var/log/ltm

Resolve the errors as they come up, repeating the above steps until your configuration really does load. At this point you will want to save the configuration.

NOTE: If you save the config and it has not loaded properly, you will erase your on disk configuration and have to start over!

tmsh save sys config

When you save your configuration we will encrypt the plain text passwords and passphrases using the new unit's master key. You will want to take a new UCS at this point, as well as running a qkview and uploading it to iHealth. This will allow you to review for known issues.