8600 to 5530 MLT Oddity

[SFSRJSTW]

I am attempting to create an MLT between our 8600 (running 5.1.7) and a 5530-24TFD running 6.2.4.010. I haev the MLT created on the 8600, and I show link on both ports on the 8600, however I only show traffic on one of the ports. On the 5530, I only show link on one port. I have already verified that all fiber jumpers and Mini-GBICS are fine as if I swap around cables, the 'working' link moves around, etc.

The 8600 MLT is:
================================================================================
Mlt Info
================================================================================
PORT SVLAN MLT MLT PORT VLAN
MLTID IFINDEX NAME TYPE TYPE ADMIN CURRENT MEMBERS IDS
--------------------------------------------------------------------------------
5 6148 SR_Servers_4_2 trunk normal norm norm 2/6,3/22 1 91 92 93 94 102 106

MULTICAST DESIGNATED LACP LACP
MLTID IFINDEX DISTRIBUTION NT-STG PORTS ADMIN OPER
--------------------------------------------------------------------------------
5 6148 disable enable 2/6 disable down


The 5530 MLT is:
Id Name Members Bpdu Mode Status Type
-- ---------------- ---------------------- ------ -------------- ------- ------
1 8600 Uplink 23-24 All Basic Enabled Trunk

I'm looking for any ideas on why this might be..

Thanks!

 

[Yaoul]

Hi,

I suggest that you check your spanning-tree configuration (should be active on MLT but not on ports ; in normal learning mode), as well as your interfaces configuration (speed / duplex - should be the same on all interfaces within the MLT, on both sides).
Cheers,

y/

 

[andy88]

Sounds like you have a faulty port or cable.

If you enable auto-negotiate on all ports you will see the faulty link go down on both ends, as a feature of auto-neg is remote fault detect.

Without this the 8600 cannot detect the fact that the remote end is down.

 

[VinceWhirlwind]

Have you added all the VLANs to the 5530 side of the Trunk?
1 91 92 93 94 102 106

And are they all tagged on both sides?

 

[dualie2012]

MLT's within Avaya Nortel are based on a source destination hash algorithm, traffic will forward on one link only and will not load share as you might expect. What you are seeing is normal behavior. Pull the one side and traffic will flip appropriately.
Also, if you are performing SMLT's with 8600 core/5X00 edge you should put in protective mechanism to protect your core from loops and broadcast storms on your network. Such mechanism are SLPP, VLACP, SLPP guard on the edge along with Fast start with bpdu filtering.

-Dualie