The following restrictions apply to an NFM-P system upgrade.

• You can upgrade an NFM-P component that is no more than two major releases older than the current release. For example, you can upgrade a Release 23 or 24 NFM-P system to Release 25, but you cannot upgrade a Release 22 system directly to Release 25; you must first perform an intermediate upgrade to at least Release 23.

• After an upgrade to an intermediate release, for example, an upgrade from Release 22 to Release 23 or 24 in preparation for a final upgrade to Release 25, you must allow each main server to initialize fully before the final upgrade, or the upgrade fails.

• A redundant system upgrade requires a network-management outage and must be performed only during a scheduled maintenance period of sufficient duration.

Note: An NFM-P server upgrade applies a default set of file permissions to each directory below the main or auxiliary server installation directory. If you change the file permissions of a directory below the main server installation directory and want the permissions to be in effect after an upgrade, you must re-apply the permissions after the upgrade.