Need help with BGP

IVB · July 30, 2008, 11:33am

I’m trying to setup BGP on my RB1000 v3.11

/routing bgp instance
add as=35714 client-to-client-reflection=no comment="" disabled=no ignore-as-path-len=no name=sdtcom \
    out-filter="" redistribute-connected=no redistribute-ospf=no redistribute-other-bgp=no redistribute-rip=\
    no redistribute-static=no router-id=82.207.85.177
/routing bgp network
add disabled=no network=194.79.8.0/22 synchronize=no
/routing bgp peer
add address-families=ip comment="" disabled=no hold-time=3m in-filter=sdtcom-in instance=sdtcom interface=\
    vlan92 multihop=yes name=telecom-lug nexthop-choice=default out-filter=sdtcom-out remote-address=\
    195.5.5.129 remote-as=6849 route-reflect=no tcp-md5-key="" ttl=255 update-source=82.207.85.177
/routing filter
add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no
add action=reject chain=sdtcom-out comment="" disabled=no invert-match=no

I need to establish BSP session and ignore all announces from peer.

But I do receive announces from peer regardless “discard” filter!

I think that there is mistake in my config - but I can’t find it by myself.

I was tryed different variants of filter:

add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no prefix=0.0.0.0

add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no prefix=0.0.0.0/0

add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no prefix=0.0.0.0 prefix-length=0

add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no prefix=0.0.0.0/0 prefix-length=0

but results was the same - I got announces (as if I don’t set filter at all).

I urgently need help!

mrz · July 30, 2008, 11:37am

/routing filter
add chain=sdtcom-in prefix=0.0.0.0/0 prefix-length=0-32 action=discard

IVB · July 30, 2008, 12:13pm

Don’t help.

/routing filter
add action=discard chain=sdtcom-in comment="" disabled=no invert-match=no prefix=0.0.0.0/0 prefix-length=0-32

Still receiving same routes. Tryed with “prefix=0.0.0.0/0” and “prefix=0.0.0.0” - don’t matter.

mrz · July 30, 2008, 12:49pm

Exactly the same rule on RB1000 is working in my setup. Make sure that chain names or any other parameters are typed in correctly.

IVB · July 30, 2008, 1:43pm

I found the problem.

Rule on your RB not the same - it differs in name

Name of chain in my case was “sdtcom-in” - don’t work. I created chain “nothing” (for testing) - it works. After some experiments i found that chains longer than 7 chars not work. “sdtcomin” - not work, “sdtcomi” - work.

But now I have another problem:

I set up another BGP session and receive several rules. But all rules come with GATEWAY-STATE unreachable, for example:

 #      DST-ADDRESS        PREF-SRC        GATEWAY-STATE GATEWAY                   DISTANCE INTERFACE
12  Db  195.5.24.0/25                      unreachable   195.5.5.129               5
13  Db  195.5.28.0/24                      unreachable   195.5.5.129               5
14  Db  195.5.44.0/24                      unreachable   195.5.5.129               5

When I checked manually - I can ping 195.5.5.129. What can I do to fix this?

IVB · July 30, 2008, 3:36pm

Another problem

I want to announce my network (with prepend) and don’t announce anything else:

/routing bgp network
add disabled=no network=194.79.8.0/22 synchronize=no
/routing filter
add action=accept chain=osdtcom comment="" disabled=no invert-match=no prefix=194.79.8.0/22 prefix-length=22 protocol="" set-bgp-prepend=5
add action=reject chain=osdtcom comment="" disabled=no invert-match=no prefix=0.0.0.0/0 prefix-length=0-32

Don’t work. No announces sent to peer.

If I don’t use filter (no checks) - announce is sent.

ricky011 · July 30, 2008, 4:19pm

i have maybe a bit off-topic, but still BGP routing specific question:

i got it to work and everything, a i’ve received all ~260000 routes (global routing table), but it seems that I am unable to find a suitable command to search/list/browse them.. in cisco ios terms this would be something like: “sh ip bgp neigh xx.xx.xx.xx received-routes | inc xxx.xx.xxx.xx/xx” is there some solution that i’ve overlooked? anyone?

mrz · July 31, 2008, 5:26am

I set up another BGP session and receive several rules. But all rules come with GATEWAY-STATE unreachable, for example:

Please read this article:
http://wiki.mikrotik.com/wiki/Using_scope_and_target-scope_attributes

i got it to work and everything, a i’ve received all ~260000 routes (global routing table), but it seems that I am unable to find a suitable command to search/list/browse them.. in cisco ios terms this would be something like: “sh ip bgp neigh xx.xx.xx.xx received-routes | inc xxx.xx.xxx.xx/xx” > > is there some solution that i’ve overlooked? anyone?

You can use print where
/ip route print where gateway=10.10.1.1 bgp=yes

IVB · July 31, 2008, 9:01am

Thanks for link - it’s helps.

How about my last question (about prepend) - can you help me?

And I have one more question: I need to receive announces from “top level” peer and resend all of them to another peer, but do not store those announces in my routing table. Which action can solve this task? I check “passthrough”, but all announces are in my routing table - it is not that I want…

farid · September 23, 2008, 11:27am

I have the same problem , did you find any solution?