These configurations on routers R3 and R4 involve the redistribution of routes between OSPF (Open Shortest Path First) and EIGRP (Enhanced Interior Gateway Routing Protocol) using route maps. Let's break down each configuration:
- The first line configures OSPF on router R3 and specifies the redistribution of EIGRP routes (process number 1) into OSPF using a route map named
set-tag.
- The subsequent lines define the
set-tagroute map. It has a single permit statement (sequence number 10) that sets the tag value to 1 for all routes being redistributed from EIGRP to OSPF.
router eigrp 1: This command enters the EIGRP router configuration mode for EIGRP Autonomous System (AS) number 1.
redistribute ospf 1: This command redistributes OSPF routes from OSPF process number 1 into the EIGRP process.
metric 2000000 1 255 1 1500: This part of the command sets the metric for the redistributed routes. The values2000000represent bandwidth and delay parameters,1represents reliability,255represents load, and1 1500represents the delay and MTU (Maximum Transmission Unit) parameters.
route-map filter-tag: This specifies the route map namedfilter-tagto be used during the redistribution.
- The subsequent lines define the
filter-tagroute map. It has two statements: - Sequence number 10 denies routes with a tag value of 1.
- Sequence number 20 permits all other routes.
In summary, the configurations on R3 and R4 involve redistributing routes between OSPF and EIGRP with the use of route maps to filter and modify the redistributed routes based on the tag values. This kind of tagging can be used to influence routing decisions and policies between the two routing protocols.