3Com Switch 7750 Series
Command Reference Guide – Routing Protocol Chapter 3 OSPF Configuration Commands
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3.1.46 router id Syntax
router id router-id
undo router id
View
System view
Parameter
router-id: Router ID, in dotted decimal notation, in the range of 0 to 255.
Description
Use the router id command to configure the ID of a router running the OSPF protocol.
Use the undo router id command to cancel the router ID that has been set.
By default, if a LoopBack interface address exists, the system chooses the LoopBack
address with the greatest IP address value as the router ID. If no LoopBack interface
is configured, the address of the physical interface with the greatest IP address value
will be the router ID.
Router ID is a 32-bit unsigned integer that uniquely identifies a router in an OSPF
autonomous system. You can specify the ID for a router. If you do not specify a router
ID, the router will automatically select one from configured IP addresses as the ID of
this router. If no IP address is configured for any interface of the router, the router ID
must be configured in OSPF view. Otherwise, OSPF protocol cannot be enabled.
When the router ID is configured manually, the IDs of any two routers cannot be same
in the autonomous system. Thus, you can select the IP address of an interface as the
ID of this router.
Related command: ospf.
Note:
A modified router ID takes effect only after OSPF is re-enabled.
Example
# Set the router ID to 10.1.1.3.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] router id 10.1.1.3