why bgp goes to state open sent and wont come up when bfd is active

[mercy_angel]

we have set on asr router cisco xr

Code Select Expand


      bgp:
      bfd fast-detect
   
      bfd multiplier 5
   
      bfd minimum-interval 300
   
     
   
    bfd:
   
      interface bundle-eth1.44
   
      echo disable
   
      rx-interval 2000000

and on mikrotik also bfd (you can see picture)


and of course bfd is checked on peer.
When i enable bfd on peer, bgp goes to open sent state and wont go up. In mikrotik logs i  can see error like neihbour not found


Where is problem?

[Otanx]

What version are you running on the Mikrotik? A quick google for "mikrotik bfd neighbor not found" shows that they had a bug in version 6. Not sure when it was fixed (or if it was). Is the Cisco IP <removed>? If so then it seems like it is sending the bfd packet, and the MikroTik is discarding it. Looking at results for mikrotik bfd in google seems that bfd has been a problem for them. I can't find any current results, but results from 2010 - 2015 seems everyone was having issues. Do you have other devices you can test with?

-Otanx

Edit: I did see this at the bottom of a page:

For interoperability with Cisco make sure to disable echo mode (it is enabled on Cisco by default), since it's not supported on MT.

To do that, on Cisco in interface configuration mode type:

no bfd echo

[mercy_angel]

What version are you running on the Mikrotik? A quick google for "mikrotik bfd neighbor not found" shows that they had a bug in version 6. Not sure when it was fixed (or if it was). Is the Cisco IP x.x.x.237? If so then it seems like it is sending the bfd packet, and the MikroTik is discarding it. Looking at results for mikrotik bfd in google seems that bfd has been a problem for them. I can't find any current results, but results from 2010 - 2015 seems everyone was having issues. Do you have other devices you can test with?

-Otanx

Edit: I did see this at the bottom of a page:

For interoperability with Cisco make sure to disable echo mode (it is enabled on Cisco by default), since it's not supported on MT.

To do that, on Cisco in interface configuration mode type:

no bfd echo

Yes it is cisco xr.
I cannot add no bfd echo, its not available on bundled interfaces, i can only echo disable like i post on the begining.
We are using 6.48.2.
Not sure whats missing

[Otanx]

We are using 6.48.2.

Then it probably isn't going to work. Based on their support forums BFD is buggy in version 6, and is scheduled to be fixed in 7.x.
Ref: https://forum.mikrotik.com/viewtopic.php?t=73195

Of course that is just a random post, but it is on the official support forums. That post is from 2015, and looking at the MikroTik site 7 is still in development. Not sure what to make of that.

-Otanx

[mercy_angel]

What do you thonk about cisco side? Everything ok?
Bfd on bundle intetfaces and bgp? I red that on bundle vlan interfaces you can only use isis, ospf and static routes.

[Otanx]

What do you thonk about cisco side? Everything ok?
Bfd on bundle intetfaces and bgp? I red that on bundle vlan interfaces you can only use isis, ospf and static routes.

It looks like it works. The MikroTik is seeing packets. Other than that I don't know. I have never done bundle interfaces.

Thanks,
-Otanx

[deanwebb]

If the BGP is buggy on v6 and v7 is in development for over 6 years, then my recommendation is to cut your losses and get a different vendor instead of Mikrotik for that function.

[Otanx]

Figured I would put this here. I ran into documentation on v7 of their software, and BFD is still not fixed. See the link below for the status of routing protocols in v7. BFD isn't the only major issue in that list. Not supporting /31s is a bigger issue in my opinion.

https://help.mikrotik.com/docs/display/ROS/v7+Routing+Protocol+Status

-Otanx