{"id":2341,"date":"2011-07-25T11:42:37","date_gmt":"2011-07-25T11:42:37","guid":{"rendered":"http:\/\/wiki.freeiz.com\/?p=2341"},"modified":"2016-08-09T12:08:27","modified_gmt":"2016-08-09T12:08:27","slug":"cisco-policy-based-routing-pbr-route-map-co","status":"publish","type":"post","link":"https:\/\/wiki-see.info\/wp\/2011\/07\/25\/cisco-policy-based-routing-pbr-route-map-co\/","title":{"rendered":"CISCO Policy based Routing (PBR) : route-map & co."},"content":{"rendered":"

Route-map can be used in a lot of application, in most of them, the aim is enabling the network engineer
\nto override\u00a0the route table and influence which way traffic flows.<\/span><\/p>\n

Below you will find a configuration sample of Policy Based Routing (PBR) we use to route different
\nsubnet through\u00a0different equipments.<\/span><\/p>\n

!<\/span><\/p>\n

\"\"<\/a><\/p>\n

<\/span><\/span><\/p>\n

!<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span>
\n !<\/span><\/p>\n

We\u2019ll route<\/span> :<\/p>\n

–\tPackets from 10.20.10.0\/24 (vlan 10) to 172.20.10.0\/24 thru Link 2<\/span>
\n–\tPackets from 10.20.20.0\/24 (vlan 20) to 172.20.10.0\/24 thru Link 1
\n<\/span>–<\/span> Other Packets thru gateway 10.20.5.254 on Gigabit Ethernet interface 3\/48<\/span><\/p>\n

Policy based routing<\/span> in Cisco Routers can be performed by using \u201c<\/span>route-map<\/span>\u201d and then applying as a
\npolicy to\u00a0the interface of the IP Packets.<\/span><\/p>\n

The route-map has a list of \u201cmatch<\/span>\u201d and \u201cset<\/span>\u201d commands where match defines the criteria under which the
\npolicy routing is performed (standard <\/span>or Extended ACL<\/span>) and set defines the actions to perform when match
\ncriteris met (i.e., set next hop<\/span>)<\/span>.<\/p>\n

I change the routing to a particular network only from a particular subnet which is defined
\nin a standard ACL<\/span>.\u00a0This ACL is then matched in a route-map and applied as an IP policy for
\nrouting change for the change in\u00a0routing behaviour.<\/span><\/p>\n

<\/strong>First Step create ACLs :<\/span><\/span><\/strong><\/p>\n

\n
\n
BraveHeart-R-C#conf t\nEnter configuration commands, one per line.  End with CNTL\/Z.\nBraveHeart-R-C(config)# access-list 100 permit ip 10.20.10.0 0.255.255.255 172.20.10.0 0.255.255.255\nBraveHeart-R-C(config)# access-list 101 permit ip 10.20.20.0 0.255.255.255 172.20.10.0 0.255.255.255\nBraveHeart-R-C(config)# access-list 102 permit ip 10.20.10.0 0.255.255.255 any\nBraveHeart-R-C(config)# access-list 102 permit ip 10.20.20.0 0.255.255.255 any<\/span><\/pre>\n<\/div>\n<\/div>\n
The access list id<\/span> doesn\u2019t matter for the matching order<\/span>.<\/p>\n
Second Step create route-map<\/span> :
\n<\/strong>
\nWe will create a route map named <\/span>Global-route map<\/span>.
\nThe matching order is the id<\/span> number of the route map 9<\/span>->10<\/span>->11<\/span><\/span><\/p>\n
\n
\n
BraveHeart-R-C#conf t\nEnter configuration commands, one per line.  End with CNTL\/Z.\nBraveHeart-R-C(config)# route-map Sample-routemap permit 9<\/span>\nBraveHeart-R-C(config-route-map)# match ip address 101\nBraveHeart-R-C(config-route-map)# set ip next-hop 10.20.6.1<\/span><\/span><\/pre>\n<\/div>\n<\/div>\n
\n
\n
BraveHeart-R-C(config)# route-map Sample-routemap permit 10<\/span>\nBraveHeart-R-C(config-route-map)#  match ip address 100\nBraveHeart-R-C(config-route-map)#  set ip next-hop 10.20.7.1<\/span><\/span><\/pre>\n<\/div>\n<\/div>\n
\n
\n
BraveHeart-R-C(config)# route-map Sample-routemap permit 11<\/span>\nBraveHeart-R-C(config-route-map)#  match ip address 102\nBraveHeart-R-C(config-route-map)# set default interface GigabitEthernet 3\/48<\/span><\/span><\/pre>\n<\/div>\n<\/div>\n
That creates a route-map called \u201cSample-routemap<\/span>\u201d and matches the ACLs 100,101,102<\/span> where the
\nsource network\u00a0for which the route-map should be actioned.<\/span><\/p>\n
Apply Policy Route-map to interface<\/span><\/strong><\/p>\n
This route-map is now applied to the interface vlan 10<\/span> and 20<\/span>.<\/span><\/p>\n
\n
\n
BraveHeart-R-C#conf t\nEnter configuration commands, one per line.  End with CNTL\/Z.\nBraveHeart-R-C(config)#int vlan 10\nBraveHeart-R-C(config-if)# ip policy route-map Sample-routemap<\/span>\nBraveHeart-R-C(config-if)#exit\n!\nBraveHeart-R-C(config)#int vlan 20\nBraveHeart-R-C(config-if)# ip policy route-map Sample-routemap<\/span>\nBraveHeart-R-C(config-if)#end<\/span><\/pre>\n<\/div>\n<\/div>\n
Now all rules configured should work (use traceroute to check the link you use<\/span> \";-)\"<\/p>\n","protected":false},"excerpt":{"rendered":"
Route-map can be used in a lot of application, in most of them, the aim is enabling the network engineer to override\u00a0the route table and influence which way traffic flows. Below you will find a configuration sample of Policy Based Routing (PBR) we use to route different subnet through\u00a0different equipments. ! ! ! ! ! […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[607],"class_list":["post-2341","post","type-post","status-publish","format-standard","hentry","category-cisco-routers","tag-route-map"],"_links":{"self":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/2341","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/comments?post=2341"}],"version-history":[{"count":1,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/2341\/revisions"}],"predecessor-version":[{"id":5065,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/2341\/revisions\/5065"}],"wp:attachment":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/media?parent=2341"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/categories?post=2341"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/tags?post=2341"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}