BGP session with Microtic

[ademir]

                   Hi ,

I'm trying to setup a bgp with a microtic equipment and it's doesn't work.

topology:

internet <-> ROUTER CISCO <-> lan <-> Microtic <->internet (other AS)

My cisco config:

router bgp 28584

bgp log-neighbor-changes

bgp bestpath compare-routerid

neighbor 200.159.169.126 remote-as 52685

neighbor 200.159.169.126 description Rafael

neighbor 200.159.169.126 ebgp-multihop 2

neighbor 200.159.169.126 disable-connected-check

neighbor 200.159.169.126 update-source Loopback0

border1#ping 200.159.169.126

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 200.159.169.126, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/9/16 ms

border1#tr 200.159.169.126

Type escape sequence to abort.
Tracing the route to 200.159.169.126

  1 wroute1.netwizard.com.br (200.159.175.2) 0 msec 0 msec 0 msec
  2 gw-conectnet.wnw.netwizard.com.br (200.159.162.5) 0 msec 0 msec 4 msec
  3 200.159.169.126 4 msec 8 msec 8 msec

003335: Apr 10 15:09:14.157 Brazil: BGP: 200.159.169.126 open failed: Connection

timed out; remote host not responding, open active delayed 26777ms (35000ms max

, 28% jitter)

003336: Apr 10 15:09:40.938 Brazil: BGP: 200.159.169.126 open active, local addr

ess 200.159.175.254 003335: Apr 10 15:09:14.157 Brazil: BGP: 200.159.169.126 open failed: Connection
timed out; remote host not responding, open active delayed 26777ms (35000ms max
, 28% jitter)
003336: Apr 10 15:09:40.938 Brazil: BGP: 200.159.169.126 open active, local addr
ess 200.159.175.254

[Harold Ritter]

Ademir,

It might just be that the microtic box doesn't have a route back to the cisco router loopback interface address. Try an extended ping using the loopback interface address. You will know right away whether it is the issue or not.

By the way, why don't you just establish the eBGP using the directly connected interface address instead of using the loopback interface address.

Regards

[ademir]

I did this test before..

border1#ping 200.159.169.126 source l0

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 200.159.169.126, timeout is 2 seconds:
Packet sent with a source address of 200.159.175.254
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/5/8 ms

border1#tr 200.159.169.126 source l0

Type escape sequence to abort.
Tracing the route to 200.159.169.126

  1 wroute1.netwizard.com.br (200.159.175.2) 0 msec 0 msec 4 msec
  2 gw-conectnet.wnw.netwizard.com.br (200.159.162.5) 0 msec 0 msec 0 msec
  3 200.159.169.126 12 msec 4 msec 8 msec

I need to have sure that cisco config is 100% correct.

[Harold Ritter]

Ademir,

There is at least an extra IP hop in the path (200.159.175.2). What is this device? Router, FW? Any change it is filtering the traffic? Could you also try increasing the value of ebgp-multihop to something higher than 2.

Regards

[ademir]

Hi,

the next hop 200.159.175.2 is a firewall, but it's not filtering bgp, just check. I increse the ebgp-multihop to 20. No efect.

[Harold Ritter]

Can you try

telnet 200.159.169.126 179 /source-interface lo0 and

telnet 200.159.169.126 179

Can you also provide the config for the microtec.

Regards

[ademir]

Case SOLVED!

The resolution was on Microtik configuration, and was with multihop. After enabling multihop on microtik, everything work fine.