Brocade TurboIron 24X Series Configuration Guide - Manual (Page 650)

616 Brocade TurboIron 24X Series Configuration Guide
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Configuring OSPF
If you are testing an OSPF configuration and are likely to disable and re-enable the protocol, you
might want to make a backup copy of the startup-config file containing the protocol 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-config file onto the flash memory.
Resetting OSPF
The clear ip ospf process all command globally resets (disables then re-enables) OSPF without
deleting the OSPF configuration information. This command is equivalent to entering the
commands no router ospf followed by router ospf. Whereas the no router ospf command disables
OSPF and removes all the configuration information for the disabled protocol from the
running-config, the router ospf command re-enables OSPF and restores the OSPF configuration
information.
The clear ip ospf process all command is useful If you are testing an OSPF configuration and are
likely to disable and re-enable the protocol. This way, you do not have to save the configuration
after disabling the protocol, and you do not have to restore the configuration by copying the backup
copy of the startup-config file onto the flash memory.
To reset OSPF without deleting the OSPF configuration, enter the following command at the Global
CONFIG level or at the Router OSPF level of the CLI.
TurboIron#clear ip ospf process all
Syntax: clear ip ospf process all
Assign OSPF areas
Once OSPF is enabled on the system, you can assign areas. Assign an IP address or number as the
area ID for each area. The area ID is representative of all IP addresses (subnets) on a router port.
Each port on a router can support one area.
An area can be normal, a stub, or a Not-So-Stubby Area (NSSA):
• Normal – OSPF routers within a normal area can send and receive External Link State
Advertisements (LSAs).
• Stub – OSPF routers within a stub area cannot send or receive External LSAs. In addition,
OSPF routers in a stub area must use a default route to the area Area Border Router (ABR) or
Autonomous System Boundary Router (ASBR) to send traffic out of the area.
• NSSA – The ASBR of an NSSA can import external route information into the area:
• ASBRs redistribute (import) external routes into the NSSA as type 7 LSAs. Type-7 External
LSAs are a special type of LSA generated only by ASBRs within an NSSA, and are flooded
to all the routers within only that NSSA.
• ABRs translate type 7 LSAs into type 5 External LSAs, which can then be flooded
throughout the AS. You can configure address ranges on the ABR of an NSSA so that the
ABR converts multiple type-7 External LSAs received from the NSSA into a single type-5
External LSA.
When an NSSA contains more than one ABR, OSPF elects one of the ABRs to perform the