Solved: Re: BGP network statement not advertising

hfakoor222 · ‎06-04-2022

Simple Topology I have

IS-IS between 4 inner routers B3 (Border) P3 (Peering) A3 (Access) C3 (Core)and BGP also

I set up most of my BGP routing policies in core router

and establish BGP peering across those 4 routers

(read below)

Now the lab is asking me to set a default route in Access Router to the Customer router, and advertise it with network statement

address-family ipv4
neighbor ibgp-rr send-community
neighbor ibgp-rr next-hop-self
neighbor 100.68.3.2 activate
distance bgp 200 200 200
no auto-summary
no synchronization
network 100.68.3.64 mask 255.255.255.192
exit-address-family




address-family ipv6
neighbor ibgpv6-rr send-community
neighbor ibgpv6-rr next-hop-self
neighbor 2001:DB8:3::2 activate
distance bgp 200 200 200
network 2001:DB8:3:4000::/52
exit-address-family
!

On Access show ip bgp

Show IPv6 bgp

This advertisement not showing up on other routers

On Core/Central Router

it's a route to self, as network statement, and same with IPV6

!
address-family ipv4
neighbor ibgp-full send-community
neighbor ibgp-full route-reflector-client
neighbor ibgp-full next-hop-self
neighbor ibgp-partial send-community
neighbor ibgp-partial route-reflector-client
neighbor ibgp-partial next-hop-self
neighbor ibgp-partial filter-list 10 out
no neighbor 2001:DB8:3::1 activate
neighbor 100.68.3.1 activate
neighbor 100.68.3.3 activate
neighbor 100.68.3.4 activate
no auto-summary
no synchronization
network 100.68.3.0 mask 255.255.255.0
network 100.68.3.28 mask 255.255.255.252
exit-address-family

And both Peering and Border router not receiving 100.68.3.x prefix advertisements, which they should be

Neighbor establishment is up

on Core router

On Peering router

I'm going to go through the run again myself, I've reset the commands 2x so far, and one time for IS-IS to be safe and no change in advertisement

Core Router

C3#sh run
Building configuration...

Current configuration : 4761 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
!
hostname C3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Lo int
ip address 100.68.3.2 255.255.255.255
ipv6 address 2001:DB8:3::2/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description Link to Peering
ip address 100.68.3.18 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex half
ipv6 address 2001:DB8:3:11::/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
interface FastEthernet1/0
description Link to Border Router
ip address 100.68.3.16 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:12::/127
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
interface FastEthernet1/1
description Link to A3 Access
ip address 100.68.3.20 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:10::/127
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
router isis as30
net 49.0001.0003.0002.00
is-type level-2-only
metric-style wide
log-adjacency-changes all
metric 100000
!
address-family ipv6
multi-topology
metric 100000
exit-address-family
!
router isis as40
is-type level-1
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
!
router bgp 30
bgp log-neighbor-changes
neighbor ibgp-full peer-group
neighbor ibgp-full remote-as 30
neighbor ibgp-full description Full Routes
neighbor ibgp-full update-source Loopback0
neighbor ibgpv6-full peer-group
neighbor ibgpv6-full remote-as 30
neighbor ibgpv6-full description Full Routes
neighbor ibgpv6-full update-source Loopback0
neighbor ibgp-partial peer-group
neighbor ibgp-partial remote-as 30
neighbor ibgp-partial description Local Routes only
neighbor ibgp-partial update-source Loopback0
neighbor ibgpv6-partial peer-group
neighbor ibgpv6-partial remote-as 30
neighbor ibgpv6-partial description Local Routes only
neighbor ibgpv6-partial update-source Loopback0
neighbor 2001:DB8:3::1 peer-group ibgpv6-full
neighbor 2001:DB8:3::1 description iBGP with Bord
neighbor 100.68.3.1 peer-group ibgp-full
neighbor 100.68.3.1 description iBGP with Border
neighbor 100.68.3.3 peer-group ibgp-partial
neighbor 100.68.3.3 description iBGP with Peering
neighbor 100.68.3.4 peer-group ibgp-partial
neighbor 100.68.3.4 description iBGP with Access
!
address-family ipv4
neighbor ibgp-full send-community
neighbor ibgp-full route-reflector-client
neighbor ibgp-full next-hop-self
neighbor ibgp-partial send-community
neighbor ibgp-partial route-reflector-client
neighbor ibgp-partial next-hop-self
neighbor ibgp-partial filter-list 10 out
no neighbor 2001:DB8:3::1 activate
neighbor 100.68.3.1 activate
neighbor 100.68.3.3 activate
neighbor 100.68.3.4 activate
no auto-summary
no synchronization
network 100.68.3.0 mask 255.255.255.0
network 100.68.3.28 mask 255.255.255.252
exit-address-family
!
address-family ipv6
neighbor ibgpv6-full send-community
neighbor ibgpv6-full route-reflector-client
neighbor ibgpv6-full next-hop-self
neighbor ibgpv6-partial send-community
neighbor ibgpv6-partial route-reflector-client
neighbor ibgpv6-partial next-hop-self
neighbor ibgpv6-partial filter-list 10 out
neighbor 2001:DB8:3::1 activate
network 2001:DB8:3::/48
network 2001:DB8:3:21::/64
exit-address-family
!
ip forward-protocol nd
ip route 100.68.3.0 255.255.255.0 Null0
no ip http server
no ip http secure-server
!
ip as-path access-list 10 permit ^$
!
!
no cdp log mismatch duplex
ipv6 route 2001:DB8:3::/48 Null0
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4
transport preferred none
!
end































Access Router







A3#sh run
Building configuration...

Current configuration : 3505 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
!
hostname A3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Loopback on Border
ip address 100.68.3.4 255.255.255.255
ipv6 address 2001:DB8:3::4/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description BackBone link to Access Router
no ip address
shutdown
duplex half
isis network point-to-point
isis metric 2
!
interface FastEthernet1/0
description Link to Peering
ip address 100.68.3.34 255.255.255.254
no ip redirects
no ip proxy-arp
duplex auto
speed auto
ipv6 address 2001:DB8:3:31::/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
!
interface FastEthernet1/1
description BackBone link to Central
ip address 100.68.3.21 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:12::1/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
router isis as30
net 49.0001.0003.0004.00
is-type level-2-only
metric-style wide
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
metric 100000
passive-interface Loopback0
!
address-family ipv6
multi-topology
set-overload-bit on-startup wait-for-bgp
metric 100000
exit-address-family
!
router bgp 30
no bgp default ipv4-unicast
bgp log-neighbor-changes
bgp deterministic-med
neighbor ibgp-rr peer-group
neighbor ibgp-rr remote-as 30
neighbor ibgp-rr description iBGP with RReflector Core
neighbor ibgp-rr update-source Loopback0
neighbor ibgpv6-rr peer-group
neighbor ibgpv6-rr remote-as 30
neighbor ibgpv6-rr description iBGP with RR
neighbor ibgpv6-rr update-source Loopback0
neighbor 2001:DB8:3::2 peer-group ibgpv6-rr
neighbor 2001:DB8:3::2 description iBGP with Core
neighbor 100.68.3.2 peer-group ibgp-rr
neighbor 100.68.3.2 description iBGP with Core
!
address-family ipv4
neighbor ibgp-rr send-community
neighbor ibgp-rr next-hop-self
neighbor 100.68.3.2 activate
distance bgp 200 200 200
no auto-summary
no synchronization
network 100.68.3.64 mask 255.255.255.192
exit-address-family
!
address-family ipv6
neighbor ibgpv6-rr send-community
neighbor ibgpv6-rr next-hop-self
neighbor 2001:DB8:3::2 activate
distance bgp 200 200 200
network 2001:DB8:3:4000::/52
exit-address-family
!
ip forward-protocol nd
ip route 100.68.3.64 255.255.255.192 100.68.3.35
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
ipv6 route 2001:DB8:3:4000::/52 2001:DB8:3:31::1
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4
transport preferred none
!
end













Peering Router




3#
P3#sh run
Building configuration...

Current configuration : 3169 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
!
hostname P3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Loopback on Border
ip address 100.68.3.3 255.255.255.255
ipv6 address 2001:DB8:3::3/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description Link to Border Router
ip address 100.68.3.19 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex half
ipv6 address 2001:DB8:3:11::1/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet1/1
no ip address
shutdown
duplex auto
speed auto
isis network point-to-point
isis metric 2
!
router isis as30
net 49.0001.0003.0003.00
is-type level-2-only
metric-style wide
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
metric 100000
passive-interface Loopback0
!
address-family ipv6
multi-topology
set-overload-bit on-startup wait-for-bgp
metric 100000
exit-address-family
!
router bgp 30
no bgp default ipv4-unicast
bgp log-neighbor-changes
bgp deterministic-med
neighbor ibgp-rr peer-group
neighbor ibgp-rr remote-as 30
neighbor ibgp-rr description iBGP with RReflector Core
neighbor ibgp-rr update-source Loopback0
neighbor ibgpv6-rr peer-group
neighbor ibgpv6-rr remote-as 30
neighbor ibgpv6-rr description iBGP with RR
neighbor ibgpv6-rr update-source Loopback0
neighbor 2001:DB8:3::2 peer-group ibgpv6-rr
neighbor 2001:DB8:3::2 description iBGP with Core
neighbor 100.68.3.2 peer-group ibgp-rr
neighbor 100.68.3.2 description iBGP with Core
!
address-family ipv4
neighbor ibgp-rr send-community
neighbor ibgp-rr next-hop-self
neighbor 100.68.3.2 activate
distance bgp 200 200 200
no auto-summary
no synchronization
exit-address-family
!
address-family ipv6
neighbor ibgpv6-rr send-community
neighbor ibgpv6-rr next-hop-self
neighbor 2001:DB8:3::2 activate
distance bgp 200 200 200
exit-address-family
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 Null0
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
ipv6 route ::/0 Null0
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4
transport preferred none
!
end

MHM Cisco World · ‎06-04-2022

remote route-ID

is 0.0.0.0 <- that meaning you config but really there is no BGP establish with neighbor.
recheck you config

View solution in original post

MHM Cisco World · ‎06-04-2022

if the BGP is flapping check the following,
1-

show ip route

can you see LO or same subnet for LO of neighbor learn from BGP neighbor (it can same neighbor or other neighbors)
then
2-

shutdown

the BGP neighbor advertise LO/subnet of LO
3-check the IGP AD with AD of BGP in first step
A-try increase the AD of IGP
B-admin to neighbor and make filter to prevent advertise LO
4-

no shut

the BGP peer

View solution in original post

MHM Cisco World · ‎06-04-2022

remote route-ID

is 0.0.0.0 <- that meaning you config but really there is no BGP establish with neighbor.
recheck you config

hfakoor222 · ‎06-04-2022

you are a lifesaver thank you

MHM Cisco World · ‎06-04-2022

and you are so so welcome friend any any time.

MHM Cisco World · ‎06-04-2022

check the Loopback you use for neighbor it must reachable for each side.

Flavio Miranda · ‎06-04-2022

Hi

"Now the lab is asking me to set a default route in Access Router to the Customer router, and advertise it with network statement"

You can do this on the A3:

neighbor x.x.x.x default-originate

x.x.x.x = Customer router

hfakoor222 · ‎06-04-2022

I am getting this error message on A3

my peering sessions seem to have gone down and the

sh ip bgp

shows no routes in all the routers whereas after I updated loopback it was fine.

I cannot ping the loopb ack

Any advice?

I will post the run commands

Core   C3

C3#sh run
Building configuration...

Current configuration : 4977 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
!
hostname C3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Lo int
ip address 100.68.3.2 255.255.255.255
ipv6 address 2001:DB8:3::2/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description Link to Peering
ip address 100.68.3.18 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex half
ipv6 address 2001:DB8:3:11::/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
interface FastEthernet1/0
description Link to Border Router
ip address 100.68.3.16 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:12::/127
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
interface FastEthernet1/1
description Link to A3 Access
ip address 100.68.3.20 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:10::/127
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
router isis as30
net 49.0001.0003.0002.00
is-type level-2-only
metric-style wide
log-adjacency-changes all
metric 100000
!
address-family ipv6
multi-topology
metric 100000
exit-address-family
!
router isis as40
is-type level-1
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
!
router bgp 30
bgp log-neighbor-changes
neighbor ibgp-full peer-group
neighbor ibgp-full remote-as 30
neighbor ibgp-full description Full Routes
neighbor ibgp-full update-source Loopback0
neighbor ibgpv6-full peer-group
neighbor ibgpv6-full remote-as 30
neighbor ibgpv6-full description Full Routes
neighbor ibgpv6-full update-source Loopback0
neighbor ibgp-partial peer-group
neighbor ibgp-partial remote-as 30
neighbor ibgp-partial description Local Routes only
neighbor ibgp-partial update-source Loopback0
neighbor ibgpv6-partial peer-group
neighbor ibgpv6-partial remote-as 30
neighbor ibgpv6-partial description Local Routes only
neighbor ibgpv6-partial update-source Loopback0
neighbor 2001:DB8:3::1 peer-group ibgpv6-full
neighbor 2001:DB8:3::1 description iBGP with Bord
neighbor 2001:DB8:3::3 remote-as 30
neighbor 2001:DB8:3::4 remote-as 30
neighbor 100.68.3.1 peer-group ibgp-full
neighbor 100.68.3.1 description iBGP with Border
neighbor 100.68.3.3 peer-group ibgp-partial
neighbor 100.68.3.3 description iBGP with Peering
neighbor 100.68.3.4 peer-group ibgp-partial
neighbor 100.68.3.4 description iBGP with Access
!
address-family ipv4
neighbor ibgp-full send-community
neighbor ibgp-full route-reflector-client
neighbor ibgp-full next-hop-self
neighbor ibgp-partial send-community
neighbor ibgp-partial route-reflector-client
neighbor ibgp-partial next-hop-self
neighbor ibgp-partial filter-list 10 out
no neighbor 2001:DB8:3::1 activate
no neighbor 2001:DB8:3::3 activate
no neighbor 2001:DB8:3::4 activate
neighbor 100.68.3.1 activate
neighbor 100.68.3.3 activate
neighbor 100.68.3.4 activate
no auto-summary
no synchronization
network 100.68.3.0 mask 255.255.255.0
network 100.68.3.28 mask 255.255.255.252
exit-address-family
!
address-family ipv6
neighbor ibgpv6-full send-community
neighbor ibgpv6-full route-reflector-client
neighbor ibgpv6-full next-hop-self
neighbor ibgpv6-partial send-community
neighbor ibgpv6-partial route-reflector-client
neighbor ibgpv6-partial next-hop-self
neighbor ibgpv6-partial filter-list 10 out
neighbor 2001:DB8:3::1 activate
neighbor 2001:DB8:3::3 activate
neighbor 2001:DB8:3::4 activate
network 2001:DB8:3::/48
network 2001:DB8:3:21::/64
exit-address-family
!
ip forward-protocol nd
ip route 100.68.3.0 255.255.255.0 Null0
no ip http server
no ip http secure-server
!
ip as-path access-list 10 permit ^$
!
!
no cdp log mismatch duplex
ipv6 route 2001:DB8:3::/48 Null0
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4
transport preferred none







A3   Router




3#
A3#sh run
Building configuration...

Current configuration : 3469 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log uptime
service password-encryption
!
hostname A3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route

A3#sh run
Building configuration...

Current configuration : 3469 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log uptime
service password-encryption
!
hostname A3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Loopback on Border
ip address 100.68.3.4 255.255.255.255
ipv6 address 2001:DB8:3::4/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description BackBone link to Access Router
no ip address
shutdown
duplex half
isis network point-to-point
isis metric 2
!
interface FastEthernet1/0
description Link to Peering
ip address 100.68.3.34 255.255.255.254
no ip redirects
no ip proxy-arp
duplex auto
speed auto
ipv6 address 2001:DB8:3:31::/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
!
interface FastEthernet1/1
description BackBone link to Central
ip address 100.68.3.21 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:12::1/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis ipv6 metric 2
!
router isis as30
net 49.0001.0003.0004.00
is-type level-2-only
metric-style wide
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
metric 100000
passive-interface Loopback0
!
address-family ipv6
multi-topology
set-overload-bit on-startup wait-for-bgp
metric 100000
exit-address-family
!
router bgp 30
no bgp default ipv4-unicast
bgp log-neighbor-changes
bgp deterministic-med
neighbor ibgp-rr peer-group
neighbor ibgp-rr remote-as 30
neighbor ibgp-rr description iBGP with RReflector Core
neighbor ibgp-rr update-source Loopback0
neighbor ibgpv6-rr peer-group
neighbor ibgpv6-rr remote-as 30
neighbor ibgpv6-rr description iBGP with RR
neighbor ibgpv6-rr update-source Loopback0
neighbor 2001:DB8:3::2 peer-group ibgpv6-rr
neighbor 2001:DB8:3::2 description iBGP with Core
neighbor 100.68.3.2 peer-group ibgp-rr
neighbor 100.68.3.2 description iBGP with Core
!
address-family ipv4
neighbor ibgp-rr send-community
neighbor ibgp-rr next-hop-self
neighbor 100.68.3.2 activate
distance bgp 200 200 200
no auto-summary
no synchronization
network 100.68.3.64 mask 255.255.255.192
exit-address-family
!
address-family ipv6
neighbor ibgpv6-rr send-community
neighbor ibgpv6-rr next-hop-self
neighbor 2001:DB8:3::2 activate
distance bgp 200 200 200
network 2001:DB8:3:4000::/52
exit-address-family
!
ip forward-protocol nd
ip route 100.68.3.64 255.255.255.192 100.68.3.35
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
ipv6 route 2001:DB8:3:4000::/52 2001:DB8:3:31::1
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4
transport preferred none
!
















B3   Router




B3#
B3#sh run
Building configuration...

Current configuration : 3187 bytes
!
upgrade fpd auto
version 12.4
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
!
hostname B3
!
boot-start-marker
boot-end-marker
!
logging message-counter syslog
!
aaa new-model
!
!
!
!
aaa session-id common
no ip source-route
no ip icmp rate-limit unreachable
ip cef
!
!
!
!
no ip domain lookup
ip domain name ws.nsrc.org
ipv6 unicast-routing
no ipv6 source-route
ipv6 cef
!
multilink bundle-name authenticated
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
archive
log config
hidekeys
!
!
!
!
!
ip tcp synwait-time 5
ip tcp path-mtu-discovery
!
!
!
!
interface Loopback0
description Loopback on Core
ip address 100.68.3.1 255.255.255.255
ipv6 address 2001:DB8:3::1/128
!
interface Null0
no ip unreachables
no ipv6 unreachables
!
interface FastEthernet0/0
description Link to Central
ip address 100.122.1.1 255.255.255.254
duplex half
ipv6 address 2001:18:0:12::1/127
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
isis network point-to-point
isis metric 2
!
interface FastEthernet1/1
description Link to Central Router
ip address 100.68.3.17 255.255.255.254
no ip redirects
no ip proxy-arp
ip router isis as30
duplex auto
speed auto
ipv6 address 2001:DB8:3:10::1/127
ipv6 nd prefix default no-advertise
ipv6 nd ra suppress
ipv6 router isis as30
isis network point-to-point
isis metric 2
isis csnp-interval 10
isis ipv6 metric 2
!
router isis as30
net 49.0001.0003.0001.00
is-type level-2-only
metric-style wide
set-overload-bit on-startup wait-for-bgp
log-adjacency-changes all
metric 100000
!
address-family ipv6
multi-topology
set-overload-bit on-startup wait-for-bgp
metric 100000
exit-address-family
!
router bgp 30
no bgp default ipv4-unicast
bgp log-neighbor-changes
bgp deterministic-med
neighbor ibgp-rr peer-group
neighbor ibgp-rr remote-as 30
neighbor ibgp-rr description iBGP with RReflector Core
neighbor ibgp-rr update-source Loopback0
neighbor ibgpv6-rr peer-group
neighbor ibgpv6-rr remote-as 30
neighbor ibgpv6-rr description iBGP with RR
neighbor ibgpv6-rr update-source Loopback0
neighbor 2001:DB8:3::2 peer-group ibgpv6-rr
neighbor 2001:DB8:3::2 description iBGP with Core
neighbor 100.68.3.2 peer-group ibgp-rr
neighbor 100.68.3.2 description iBGP with Core
!
address-family ipv4
neighbor ibgp-rr send-community
neighbor ibgp-rr next-hop-self
neighbor 100.68.3.2 activate
distance bgp 200 200 200
no auto-summary
no synchronization
exit-address-family
!
address-family ipv6
neighbor ibgpv6-rr send-community
neighbor ibgpv6-rr next-hop-self
neighbor 2001:DB8:3::2 activate
distance bgp 200 200 200
exit-address-family
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
!
no cdp log mismatch duplex
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
transport preferred none
stopbits 1
line vty 0 4

MHM Cisco World · ‎06-04-2022

if the BGP is flapping check the following,
1-

show ip route

can you see LO or same subnet for LO of neighbor learn from BGP neighbor (it can same neighbor or other neighbors)
then
2-

shutdown

the BGP neighbor advertise LO/subnet of LO
3-check the IGP AD with AD of BGP in first step
A-try increase the AD of IGP
B-admin to neighbor and make filter to prevent advertise LO
4-

no shut

the BGP peer

hfakoor222 · ‎06-04-2022

Thank you again you saved me

Shutting down the core facing interfaces then resetting the network advertisement, then turing on the interfaces did the trick

This became an issue after I changed the Loopback so I am not sure if the network statement itself was affected because of this, but I see there's a lot going on in this lab so shutting down the interfaces and refreshing the routes did the trick.

Now all my prefixes being advertised as well.