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BGP Configuration Commands
6-96 Configuring the Border Gateway Protocol
Syntax of the “no” Form
Thenoformofthiscommandremovesthespecifiedneighbor:
no neighbor {ip-address | peer-group-name} filter-list filter-list
Mode
Routerconfiguration:XSR(config-router)#
Example
Thisexampleappliesfilterlist1toincomingadvertisementsfromneighbor192.168.1.1.Only
routeswhichstartwithASpath200andendwithASpath500willbeacceptedfromtheneighbor.
XSR(config)#ip as-path access-list 1 permit “^200 .* 500$”
XSR(config)#router bgp 100
XSR(config-router)#neighbor 192.168.1.1 remote-as 101
XSR(config-router)#neighbor 192.168.1.1 filter-list 1 in
neighbor maximum-prefix
Thiscommandcontrolsthenumberofprefixesreceivedfromaparticularneighbor.Whenthe
maximumnumberofprefixesisexceeded,aCEASEmessageissentandtheconnectioniscleared.
Toreactivatethesession,enter
clear ip bgp <IP address>.Ifthenumberofprefixesissetto
zero,noprefixeswillbeacceptedfromtheneighbor.
Syntax
neighbor {ip-address | peer-group-name} maximum-prefix value [threshold][warning-
only]
peer-group-name
BGPpeergroupbyname.Range:1to64characters.
filter-list
IdentifiestheASpathaccesslist.Rangeis1‐199.
in
Filterlistisappliedtoinboundroutes.
out
Filterlistisappliedtooutboundroutes.
weight
Assignsaweighttoallroutesmatchingthefilterlist.
value
Weightrangefrom0to65535.
ip-address
Neighbor’sIPaddress.
peer-group-name
BGPpeergroupbyname.Range:1to64characters.
value
Maximumnumberofprefixesthatcanbereceivedfromaneighbor,
rangingfrom1to4,294,967,295.
threshold
Thethresholdvalue‐percentageofmaximum‐atwhichawarningis
generated,rangingfrom1to100prefixes.
warning-only
WhenthemaximumnumberofprefixesisreachedtheXSRgeneratesa
warningmessageinsteadofterminatingthepeeringsession.