Understanding the effects of disabling OSPFv2

Consider the following before disabling OSPFv2 on a device:

• If you disable OSPFv2, the device removes all the configuration information for the disabled protocol from the running configuration. Moreover, when you save the configuration to the startup configuration file after disabling one of these protocols, all the configuration information for the disabled protocol is removed from the startup configuration file.
• If you have disabled the protocol but have not yet saved the configuration to the startup configuration file and reloaded the software, you can restore the configuration information by re-entering the router ospf command, or by selecting the Web management option to enable the protocol. If you have already saved the configuration to the startup configuration file and reloaded the software, the information is gone.
• If you are testing an OSPFv2 configuration and are likely to disable and re-enable the protocol, you might want to make a backup copy of the startup configuration file containing the protocol’s configuration information. This way, if you remove the configuration information by saving the configuration after disabling the protocol, you can restore the configuration by copying the backup copy of the startup configuration file into the flash memory.