Filter
Top Products
Alteon OS Application Guide
202
Chapter 12: OSPF 42C4911, January 2007
6. Assign MD5 key ID to OSPF virtual link on switches 2 and 4.
Host Routes for Load Balancing
Alteon OS implementation of OSPF includes host routes. Host routes are used for advertising
network device IP addresses to external networks, accomplishing the following goals:
ABR Load Sharing
As a form of load balancing, host routes can be used for dividing OSPF traffic among mul-
tiple ABRs. To accomplish this, each switch provides identical services but advertises a
host route for a different IP address to the external network. If each IP address serves a dif-
ferent and equal portion of the external world, incoming traffic from the upstream router
should be split evenly among ABRs.
ABR Failover
Complementing ABR load sharing, identical host routes can be configured on each ABR.
These host routes can be given different costs so that a different ABR is selected as the
preferred route for each server and the others are available as backups for failover pur-
poses.
Equal Cost Multipath (ECMP)
With equal cost multipath, a router potentially has several available next hops towards any
given destination. ECMP allows separate routes to be calculated for each IP Type of Ser-
vice. All paths of equal cost to a given destination are calculated, and the next hops for all
equal-cost paths are inserted into the routing table.
If redundant routes via multiple routing processes (such as OSPF, RIP, BGP, or static routes)
exist on your network, the switch defaults to the OSPF-derived route.
>> # /cfg/l3/ospf/virt 1/mdkey 2