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MPLS (LDP) and Juniper interoperability failure

Posted: Tue Mar 03, 2009 1:48 pm
by bofh666ie
Hi,

I've been testing MPLS interoperability between ROS 3.20 (routing-test/mpls-test) and a Juniper J2300 (JUNOS 8.4 and 9.4ES).
Results so far:

LDP adjacency is not being established. The Mikrotik neigbour shows in the Juniper, but no label information is being exchanged. On the MT, mpls ldp neigbour print does not show the Juniper neighbour.

I'll test again when 3.21 is out...

rgds,
bofh

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Tue Mar 03, 2009 5:52 pm
by Eising
Hmm, I have a feeling it has something to do with the way Juniper distributes it's labels.
From the juniper-nsp list, I found the following information:
Label distribution control mode: ordered (not sure)
Label retention mode: liberal
Label advertisement mode: downstream unsolicited
(http://www.mail-archive.com/juniper-nsp ... 05038.html)

If you check out the MPLS presentation from Prague, you will notice that the list of unsupported LDP features has the following items:
  • Downstream on demand
  • Ordered label distribution protocol
It is quite possible that (at least) one of these two features are in use by the Juniper LDP implementation.

Although I lurk the juniper-nsp list, I am by no means a juniper expert. My JNCIA book did not mention a way to change the LDP parameters, and as I don't have access to the restricted part of the juniper website, I cannot help you any further.

Anyway, this is just my theory.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Tue Mar 03, 2009 6:28 pm
by bofh666ie
Well, well, well...

as it turns out, these configuration parameters exist in JUNOS. The commands are hidden and undocumented.

Every day is a school day... Back to the testing lab.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Fri Mar 06, 2009 12:19 am
by bofh666ie
Right,

after enabling control-mode independent on the J2300 LDP still doesn't establish an adjacency. The neigbour comesup briefly (until hold time runs out) butno labels or routes exchanged.

next test with 3.21...

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Fri Mar 06, 2009 8:48 am
by Eising
Interesting. I had no problems getting it work, almost out of the box, against a Cisco 7600...
Keep us posted with whatever you find out.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Fri Mar 06, 2009 3:52 pm
by Mplsguy
bofh,
It would be great if you could capture adjacency establishment packet exchange and send to support@mikrotik.com.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Fri Mar 06, 2009 11:28 pm
by nz_monkey
It would be good to hear the results on this.

Down here in Australia and New Zealand, if it's MPLS it will be Juniper.

Cisco is seen here as an Enterprise product, where as Juniper is seen as a Carrier product.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Mon Mar 09, 2009 7:36 pm
by Mplsguy
This problem is caused by RouterOS not supporting LDP graceful restart feature and improperly refusing to complete LDP session initialization with Juniper router reporting this feature. This problem will be fixed in next release of mpls-test. LDP graceful restart feature is on MPLS todo list.

Re: MPLS (LDP) and Juniper interoperability failure

Posted: Tue Mar 10, 2009 12:52 am
by bofh666ie
Excellent!

after disabling both graceful-restart and graceful-restart-helper on JunOS,

[edit protocols ldp]
graceful-restart {
disable;
helper-disable;
}

the session is up and exchanging labels.

I'll test with it enabled on 3.21

cheers,
bofh