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Allied Telesis X8100, x908 manual Shut down the neighbor, and then bring it up again, a neighbor

Models: X8100 x908

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4. Shut down the neighbor, and then bring it up again.

BGP: Configuring AS Path Filters

4. Shut down the neighbor, and then bring it up again.

awplus(config-router)#neighbor 45.45.45.46 shutdown awplus(config-router)#neighbor 45.45.45.46 no shutdown

5.Check that the IP route table does not have the BGP routes from the AlliedWare neighbor in AS 34568 any more.

awplus(config-router)# do show ip route

Codes: C - connected, S - static, R - RIP, B - BGP O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2

* - candidate default

C45.45.45.0/24 is directly connected, vlan1

C 64.0.0.0/4 is directly connected, vlan64

Explicitly include
a neighbor	6. Add an entry to the an AS path access list that explicitly includes AS 34568.

	awplus(config)#	ip as-path access-list list1 permit 34568
	awplus(config)#

7.Shut down the neighbor, and then bring it up again.

awplus(config-router)#neighbor 45.45.45.46 shutdown awplus(config-router)#neighbor 45.45.45.46 no shutdown

8.Check that the IP route table has the BGP routes from the AlliedWare neighbor in AS 34568 again.

awplus(config-router)# do show ip route

Codes: C - connected, S - static, R - RIP, B - BGP O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2

* - candidate default

B45.0.0.0/8 [20/0] via 45.45.45.46, vlan1, 00:00:03

C45.45.45.0/24 is directly connected, vlan1

B52.0.0.0/8 [20/0] via 45.45.45.46, vlan1, 00:00:03

C64.0.0.0/4 is directly connected, vlan64

Use Route Maps and Other Filters to Filter and Alter BGP and OSPF Routes Page 19

Image 19

Allied Telesis X8100, x908 manual Shut down the neighbor, and then bring it up again, a neighbor

Contents

Technical Guide IntroductionBGP Applying Route Maps to Imported Routes ContentsIntroduction Which products and software version does it apply to?Which products and software version does it apply to? Related How To NotesBGP Concepts and Terminology BGP updatesBGP peers Next-hop Update attributesOrigin AS-pathDistribute filters Access Control List ACL filtersBGP Overview of the Available Filter Types Filter typesDifference and Relationship in BGP Examples for filtering BGP Update messages Example AS path filters on page  Example Prefix filters on page Hierarchy of the Different FiltersBGP Example  Example Distribute filters on pageBasic configuration awplus#show ip route Confirming the neighbor relationshipAlliedWare switch AlliedWare Plus switchAbout ACLs BGP Configuring Distribute FiltersExample Distribute filters Using ACLs as filtersFilter out one particular route from a neighbor Filter out a range of prefix lengths 3. Check that the IP route table now includes all the routes awplusconfig# neighbor 45.45.45.46 distribute-list list2 inawplusconfig-router# do show ip route awplusconfig# router bgpUse a numbered ACL instead of a named ACL 4. Check that the IP route table no longer includes 52.0.0.0/8 awplusconfig-router# do show ip routeAS path lists BGP Configuring AS Path FiltersExample AS path filters Using AS path lists as path filtersDiscard or allow routes from a neighbor a neighbor 4. Shut down the neighbor, and then bring it up again7. Shut down the neighbor, and then bring it up again An outgoing filter that uses an AS-path list Another exampleBGP Configuring AS Path Filters About prefix lists BGP Configuring Prefix FiltersMask length awplusconfig-router# neighbor neighbor prefix-list list-name out Using prefix lists as prefix filtersExample Prefix filters awplusconfig-router# neighbor neighbor prefix-list list-name inFilter out a range of different prefix lengths awplusconfig-router# do show ip route BGP Configuring Prefix FiltersStructure of a route map BGP Configuring Route MapsClauses Configuring a match clauseAn AS path list Case A community listCase One or more prefixes, by using an ACL One or more prefixes, by using a prefix listA metric the MED attribute Configuring a set clauseA next hop address An originset community community-values additive set ip next-hop ipadd set weightset atomic-aggregate set extcommunity rtsoo ext-comm-numberA match clause and one or more set clauses The effect of different combinations of clausesOne match clause with an action No match clause and one or more set clausesRouter AS Update from PeerUpdate 1 to Peer Update 2 to PeerFirst, enter BGP router mode for the AS. The prompt should look like awplusconfig-route-map#set metric ExamplesExample B Match on a prefix-list that denies an entry awplusconfig#ip prefix-list test1 permit 52.0.0.0/84. Apply this route map as the in route map on the neighbor awplusconfig-route-map#router bgp Example D Matching on a next-hop prefix-listExample E Prepending AS numbers awplusconfig-route-map#match ip addressset bgp peer=45.45.45.45 outroutemap=com sendcommunity=yes 1. Configure the AW peer to send out a community numberThe routes coming from that peer has community add ip routem=com entry=1 set commmun=8989BGP#show ip route set bgp peer=45.45.45.45 outroutemap=mixed sendcommunity=yes 8. Add that ACL as a distribute-list in-filter on the neighbor route-map marker permit Examples Route maps ACLs Path filters Prefix filtersSyntax BGP Applying Route Maps to Imported Routesnetwork neighbor default-originateOther Uses of Route Maps neighbor unsuppress-mapRoute map configuration BGP configurationBGP Route Map Filtering Example set local-preference route-map outdef permit Configuring a match clause OSPF Configuring Route Maps for Filtering and Modifying OSPF RoutesMetric InterfaceConfiguring a set clause A prefix, by using a prefix listA prefix, by using an ACL External route type Set the metric, by using the command set metric OSPF Applying Route Maps