Route Maps
385
where routemail is an arbitrary name chosen for the route map, 10 is the
route map sequence number, and the sequence number is 10 by default,
unless another number is specified.
We will now set the criteria for the first match clause:
match ip address 101
where 101 is the access list that the match clause is checking traffic against.
We will now use the set clause to specify the next-hop address of traffic
satisfying the match clause:
set ip next-hop 172.16.2.2
where 172.16.2.2 is the IP address of the next-hop router.
Finally, we need to specify where to send traffic if the match condition is
not met:
route-map routemail permit 20
set ip next-hop 172.16.1.2
where 20 is the sequence number and 172.16.1.2 is the next-hop router.
RouterA will now send all SMTP traffic over the 56Kbps link to RouterC and
all other traffic over the 1.544Mbps link to RouterB, as shown in Figure 10.13.
F I G U R E 1 0 . 1 3
Policy routing configuration for example 1
Internet
access-list 101 permit tcp any any eq 25
!
route-map routemail permit 10
match ip address 101
set ip next-hop 172.16.2.2
!
route-map routemail permit 20
set ip next-hop 172.16.1.2
172.16.2.2/24
172.16.1.2/24
56Kbps link
SMTP
WWW, FTP, etc.
1.544Mbps link
172.16.1.1/24
172.16.2.1/24
s1
s0
ISP A
RouterB
ISP B
RouterC
Company A
RouterA
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