Changing the network environment may happen as often as, say, the administrative passwords get change, but when it happens, then the environment change directly affects database and Enterprise Manager availability, which can adversely affect the smooth operation of the site. When the environment changes you must be aware of the consequences these changes will bring and how to restore the service as soon as possible.
Changing the IP address means Enterprise Manager Console won't be available and it won't be possible to start it; all the Oracle connectivity configuration files are affected too.
As this is an administrative change, it is strongly suggested to backup the current environment by taking a full Oracle Home and database backup. This will back-up the current configuration files as well as the current EM repository.
The procedure used to get the environment working is as follows:
1. Shut down enterprise manager, the database and...