We have a MT 3.27 trying to peer with a ZEBOS/Quagga based router
Both systems have AS nos < 65535


Apparently zebos uses a 2 byte AS number. The zebos version we use does NOT support 4 byte AS numbers, only 2. We had the same issue with our Cisco 7606 router when we updated the IOS last month. We had to contact Cisco and they gave us a fix. For that, it was to enter “neighbor x.x.x.x dont-capability-negotiate” in the 7606 (not the zebos) to stop it from trying to negotiate the AS byte capability.


It seems mikrotik does not support the command how do we get this working with the ZEBOS/QUAGGA implementation.

is your Cisco peers to MT or Zebos?..

Well the Cisco peers fine with ZEBOS after the command. We need MT to peer with ZEBOS

something like this. Cisco and MT and not connected and independent .

Cisco<-> zebos
MT<->zebos

if problem with negotiation appeared on MT & Cisco, then the reason is in Zebos. you need fix for Zebos, not Cisco/MT

Cisco has a command that allows older non as4 capability negotiation in bgp . MT should also be having some command to support this shouldnt it ?

Cisco has workaround to NOT negotiate the capabilities. ROS hasn't such workaround, it works by standard =)

Basically zebos is quagga and quagga has similar commands for negiotiation.
http://www.quagga.net/docs/docs-multi/C ... ation.html

Since MT doesnot have those commands even though I have zebos setup right MT cant connect !

just looked at topic's subject... error 65 - where do you see that?

ON the zebos. BTW we are using routing-test packages, in 3.13 the 4 byte AS was added to the routing-test.

well, since negotiation is not enforcement, it's only Zeros problem - Zeros should ignore unknown capabilities, but not show en error

Well how can we force mikrotik to only do 2 byte AS and not send 4 byte AS capability ?

In latest version BGP capability check was turned off, so it should work.

What is the latest version ? We are using 3.27 . Latest is 3.28 will that run this . I will try it.

So it also does not advertise the capaibility to peers for AS4 capaibility ?

You have to wait a little longer. First time RouterOS will try to connect and check capabilities, then if it fails next time it will try to connect and ignore capabilities.

If it is still not connected after several tries, then please contact support@mikrotik.com

Was this issue fixed in 3.28 ?

again, it's not an issue =)

have you tried 3.28? what's in Log?

Same problem in 3.28 nothing changed. I am stuck .. if its an older bgp implentation supporting only as2 we should not even send as4 capability ...

we should not even send as4 capability ...

capability should be always sent if it's supported. it's what negotiation is for. if other side don't know this capability, it should ignore that

again,

what's in Log?