712 | Open Shortest Path First (OSPFv2 and OSPFv3)w w w . d e l l . c o m | s u p p o r t . d e l l . c o m Configure OSPF Stub-Router AdvertisementConfigure OSPF Stub-Router Advertisement is supported on platforms: c eWhen you bring a new router onto an OSPF network, you can configure the router to function as a stubarea by globally reconfiguring the OSPF link cost so that other routers do not use a path that forwardstraffic destined to other networks through the new router for a specified time until the router’s switchingand routing functions are up and running, and the routing tables in network routers have converged.By using the max-metric router-lsa command, you force the link cost of all OSPF non-stub links to themaximum link cost (65535) for a specified time. The advertisement of this maximum metric causes otherrouters to assign a cost to the new router that is higher than the cost of using an alternate path. Because ofthe high cost assigned to paths that pass through the new router, other routers will not use a path throughthe new router as a transit path to forward traffic to other networks.Use the max-metric router-lsa command to gracefully shut down or reload a router without droppingpackets destined for other networks.Command Syntax Command Mode Usagemax-metric router-lsa[on-startup {announce-time |wait-for-bgp [wait-time]}]ROUTER OSPF E-Series ExaScale only: Configure the maximum cost of65535 on a new router so that it always functions as a stubrouter in the network and OSPF traffic destined to othernetworks is not routed on paths which pass through therouter.on-startup announce-time specifies the time (inseconds) following boot-up during which themaximum cost (65535) for transmitting OSPF trafficon router interfaces is announced in LSAs and therouter functions as a stub router.Range: 5 to 86400 seconds.on-startup wait-for-bgp [wait-time] enables the routerto announce the maximum metric in OSPF LSAs untilthe BGP routing table converges with updatedroutes. Default: 600 seconds.You can also specify the time (in seconds) that therouter waits for the BGP routing table to convergebefore it stops advertising the maximum cost in LSAsand advertises the router’s currently configuredOSPF cost. Range: 5 to 86400 seconds.Note: If you enter the max-metric router-lsa command without an option (on-startup announce-time oron-startup wait-for-bgp [wait-time]), the maximum metric of 65535 is always announced in LSAs sent by therouter.
