bgb over frame-relay

[ccobtn]

Hi All,

I have tow routers frame-relay back to back and configuring bgp. The problem is that no bgp connection/routing update between the two routers.

here is the config

nterface Loopback1

ip address 10.0.199.1 255.255.255.255

!

interface FastEthernet0/0

no ip address

shutdown

duplex auto

speed auto

!

interface FastEthernet0/1

ip address 10.1.199.242 255.255.255.240

speed 100

full-duplex

!

interface Serial0/3/0

bandwidth 2048

no ip address

encapsulation frame-relay IETF

no keepalive

frame-relay lmi-type ansi

!

interface Serial0/3/0.1 point-to-point

ip unnumbered Loopback1

frame-relay interface-dlci 101 IETF

!

router bgp 100

no synchronization

bgp log-neighbor-changes

network 10.0.199.1 mask 255.255.255.255

network 10.1.0.0 mask 255.255.0.0

timers bgp 10 30

neighbor 10.0.199.2 remote-as 200

neighbor 10.0.199.2 update-source Loopback1

no auto-summary

!

................bgp upadte...................

w2-5-r01#sh ip bgp neighbors

BGP neighbor is 10.0.199.2, remote AS 100, external link

BGP version 4, remote router ID 0.0.0.0

BGP state = Active

Last read 00:53:24, hold time is 30, keepalive interval is 10 seconds

Configured hold time is 30,keepalive interval is 10 seconds, Minimum holdtime

from neighbor is 0 seconds

Message statistics:

InQ depth is 0

OutQ depth is 0

Sent Rcvd

Opens: 0 0

Notifications: 0 0

Updates: 0 0

Keepalives: 0 0

Route Refresh: 0 0

Total: 0 0

Default minimum time between advertisement runs is 30 seconds

For address family: BGP IPv4

BGP table version 2, neighbor version 0/0

Output queue size : 0

Index 1, Offset 0, Mask 0x2

1 update-group member

Sent Rcvd

Prefix activity: ---- ----

Prefixes Current: 0 0

Prefixes Total: 0 0

Implicit Withdraw: 0 0

Explicit Withdraw: 0 0

Used as bestpath: n/a 0

Used as multipath: n/a 0

Outbound Inbound

Local Policy Denied Prefixes: -------- -------

Total: 0 0

Number of NLRIs in the update sent: max 0, min 0

Connections established 0; dropped 0

Last reset never

External BGP neighbor may be up to 2 hops away.

No active TCP connection

.................neigh router.............................

interface Loopback1

ip address 10.0.199.2 255.255.255.255

!

interface FastEthernet0/0

no ip address

shutdown

duplex auto

speed auto

!

interface FastEthernet0/1

ip address 10.2.199.242 255.255.255.240

speed 100

full-duplex

!

interface Serial0/3/0

bandwidth 2048

no ip address

encapsulation frame-relay IETF

no keepalive

frame-relay lmi-type ansi

!

interface Serial0/3/0.1 point-to-point

ip unnumbered Loopback1

frame-relay interface-dlci 102 IETF

!

router bgp 200

no synchronization

bgp log-neighbor-changes

network 10.0.199.1 mask 55.255.255.255

network 10.2.0.0 mask 255.255.0.0

timers bgp 10 30

neighbor 10.0.199.1 remote-as 100

neighbor 10.0.199.1 update-source Loopback1

no auto-summary

I was told to add nei x.x.x.x ebgp muilthop 3 for both routers, i have added this but still the bgp on both router don't see local network but see loopback ip addess and no bgp connection between the routers

Regards

[Harold Ritter]

Have you been able to ping from one loopback to the other? Because you are using "ip unnumbered" on the freme-relay point-to-point, you should probably have a static route on each router pointing at the other as follow:

rtr1:

ip route 10.0.199.2 255.255.255.255 Serial0/3/0.1

rtr2:

ip route 10.0.199.1 255.255.255.255 Serial0/3/0.1

You could also remove the ip unnumbered on the frame-relay link and replace it by an ip address.

Hope this helps,

[ccobtn]

Hi,

I added static routes and changed dlci so that both end have same number. Now router can est bgp connection but both bgp routers can't see/advt their local network 10.1.199.0/28 and 10.2.199.0/28 respectively.

bgp-routes

gw2-5-r01#sh ip rou

10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

C 10.2.199.240/28 is directly connected, FastEthernet0/1

S 10.0.199.1/32 is directly connected, Serial0/3/0.1

C 10.0.199.2/32 is directly connected, Loopback1

gw2-5-r01#sh ip bg

gw2-5-r01#sh ip bgp

BGP table version is 7, local router ID is 10.0.199.2

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

r> 10.0.199.1/32 10.0.199.1 0 0 100 i

*> 10.0.199.2/32 0.0.0.0 0 32768 i

gw2-5-r01#

w1-5-r01#sh ip rou

Gateway of last resort is not set

10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

C 10.1.199.240/28 is directly connected, FastEthernet0/1

C 10.0.199.1/32 is directly connected, Loopback1

S 10.0.199.2/32 is directly connected, Serial0/3/0.1

gw1-5-r01#sh ip bgp

BGP table version is 4, local router ID is 10.0.199.1

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 10.0.199.1/32 0.0.0.0 0 32768 i

r> 10.0.199.2/32 10.0.199.2 0 0 200 i

gw1-5-r01#

regards

Regards

[Kevin Dorrell]

Have you tried network 10.1.199.0 mask 255.255.255.240 ? I think both the subnet base and the mask must match exactly the network you want to advertise.

Kevin Dorrell

Luxembourg

[vcjones]

Unlike interior gateway protocols like EIGRP and OSPF, where any prefix contained in the "network" statement will be advertised, in BGP, the line "network 10.2.0.0 mask 255.255.0.0" will only advertise the prefix 10.2/16 and NO others. To advertise 10.2.199.240/28 you need to use the line "network 10.2.199.240 mask 255.255.255.240" instead.

Don't feel too embarrassed, it is probable that every BGP newbie has been bitten by this behavior. Been there, done that, been burnt :-)

Note also that in your case, you could also avoid the problem by adding the line "redistribute connected" to your BGP configuration.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com

[ccobtn]

Hi,

Thanks for your explanation, I’m not embarrassed at all I guess this is how we all learn (learn from our mistakes) and hopefully I won’t be bitten twice!!!.

Regards

[vcjones]

Execute the command "show ip route 10.0.199.2" on your first router. The answer should tell you what your problem is. You need to fix it with an explicit route (either learned via an interior gateway protocol or defined by a static route). One other gotcha is that the route must be explicit. BGP will not use the default route for neighbor set up.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com

[ccobtn]

Hi,

Hi,

Thanks, i have added static routes for both network and bgp is working fine now.

it's looks like any network that falls outside mayor subnets /8/16/24 will need to have explicit static route.......is reason for this ???.

Regards

[Harold Ritter]

The IOS tries to match the network statement with a RIB entry in order to originate the prefix. It has to be a perfect match for it to work. The rule for the network is as follow:

If you specify a mask, IOS taks this mask in consideration. If you don't the classfull mask is used (ie class A = 8bits, B = 16 and C = 24).

Hope this helps,