Users Guide

neighbor {ip-address | ipv6–address | peer-group-name} maximum—prefix maximum [threshold]
[warning-only]as-number
Example of conguring both IPv4 and IPv6 VRF address families
The following are the sample steps performed to congure a VRF, and VRF address families for IPv4 (unicast and multicast) and IPv6.
DellEMC(conf)# ip vrf vrf1
DellEMC(conf-vrf)# ip route-import 200:5
DellEMC(conf-vrf)# exit
DellEMC(conf)# router bgp 100
DellEMC(conf-router_bgp)# address-family ipv4 vrf vrf1
DellEMC(conf-router_bgp_af)# neighbor 50.0.0.2 remote-as 200
DellEMC(conf-router_bgp_af)# neighbor 50.0.0.2 maximum-prefix 10000 warning-only
DellEMC(conf-router_bgp_af)# neighbor 50.0.0.2 no shutdown
DellEMC(conf-router_bgp_af)# exit
DellEMC(conf-router_bgp)# address-family ipv6 unicast vrf vrf1
DellEMC(conf-router_bgpv6_af)# neighbor 50.0.0.2 activate
DellEMC(conf-router_bgpv6_af)# exit
DellEMC(conf-router_bgp)# address-family ipv4 multicast vrf vrf1
DellEMC(conf-router_bgpv6_af)# neighbor 50.0.0.2 activate
DellEMC(conf-router_bgp)# exit
Following is the output of show ip bgp vrf vrf1 summary command for the above conguration.
DellEMC#show ip bgp vrf vrf1 summary
BGP router identifier 1.1.1.1, local AS number 100
BGP local RIB : Routes to be Added 0, Replaced 0, Withdrawn 0
1 neighbor(s) using 16384 bytes of memory
Neighbor AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/Pfx
50.0.0.2 200 0 0 0 0 0 00:00:00 0
Following is the output of show running-config bgp command for the above conguration.
DellEMC#show running-config bgp
!
router bgp 10
bgp router-id 1.1.1.1
network 10.10.21.0/24
bgp four-octet-as-support
neighbor 20.20.20.1 remote-as 65550
neighbor 20.20.20.1 no shutdown
!
address-family ipv4 vrf vrf1
neighbor 50.0.0.2 maximum-prefix 10000 warning-only
neighbor 50.0.0.2 remote-as 200
neighbor 50.0.0.2 no shutdown
exit-address-family
!
address-family ipv4 multicast vrf vrf1
neighbor 50.0.0.2 activate
exit-address-family
!
address-family ipv6 unicast vrf vrf1
neighbor 50.0.0.2 activate
exit-address-family
DellEMC#
Route-refresh and Soft-reconguration
BGP soft-reconguration allows for faster and easier route changing.
Changing routing policies typically requires a reset of BGP sessions (the TCP connection) for the policies to take eect. Such resets cause
undue interruption to trac due to hard reset of the BGP cache and the time it takes to re-establish the session. BGP soft recong allows
for policies to be applied to a session without clearing the BGP Session. Soft-recong can be done on a per-neighbor basis and can either
be inbound or outbound.
Border Gateway Protocol (BGP)
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