Tech Tip - Dynamic Routing: Router-ID

[Chris_Atkinson]

Background:

The Router ID concept is used by both the OSPF and BGP protocols.
The Router ID is different to the process ID or autonomous system number. The Router ID uniquely identifies the router within the autonomous system. Commonly with traditional routing vendors devices this might be aligned to an IP address of a Loopback interface since those don't go down.

To ensure stable operation of dynamic routing protocols in GAiA OS configure the Router ID explicitly, rather than relying on the default (automatic) setting. Setting the Router ID prevents the ID from changing if the default interface used for the router ID goes down. Incorrectly set Router ID values can also cause unexpected behavior during cluster failovers.

Important:

• Do not use the IP addresses 0.0.0.0 or 127.X.Y.Z as the Router ID value.
• In a cluster, you must configure the Router ID to one of the Cluster Virtual IP addresses (VIP).
• In a Cluster, you must configure all the Cluster Members in the same way.

Note changing the Router ID retroactively in GAiA OS is cumbersome, typically requires removal and reconfiguration of much of the routing protocol configuration.

An alternate process leveraging internal dbset commands is available via TAC / ATAM to help workaround this if required.

OSPF Router ID:

sk183316: "No Global Router ID configured" error when configuring OSPF peers in Gaia OS after an upg...

Check Point R82 Advanced Routing Admin Guide - OSPF Configuring Router-ID

BGP Router ID:

sk183315: "No Global Router ID configured" error when configuring BGP peers in Gaia OS after an upgr...

Check Point R82 Advanced Routing Admin Guide - BGP Configuring in Gaia Portal BGP Global Settings

[the_rock]

Definitely great tip Chris. I had seen people make mistake with this ID, though it would seem its pretty straight forward from the documentation : - )