VLAN trunking problem

frank.murray · ‎11-09-2007

I've got a Cat4000 connected to a CAT6509- GigE connection with 802.1q

trunking. I have connectivity but about a dozen users on the 4000 can't connect to the network. It doesn't track to a single blade. On the 4000 I can see the users MAC address in the CAM table, but not on the CAM table on the 6509.

allan.thomas · ‎11-09-2007

Could you post the configurations of the trunks ports on the 4000 and 6500.

Have verified that the VLAN which these users are associated with exists on the 6500 and is allowed on the trunk?

Incidentally is there any other connectivity across this trunk for other VLANs.

Regards

Allan.

frank.murray · ‎11-09-2007

all vlans are permitted. there are many hosts connecting across the trunk- just not some.

CAT4000 (enable) show trunk

* - indicates vtp domain mismatch

Port Mode Encapsulation Status Native vlan

-------- ----------- ------------- ------------ -----------

1/1 on dot1q trunking 1

Port Vlans allowed on trunk

-------- ---------------------------------------------------------------------

1/1 1-1005

Port Vlans allowed and active in management domain

-------- ---------------------------------------------------------------------

1/1 1-2,4,6-7,13,15-16,20,23-27,33,153,209,224,254

Port Vlans in spanning tree forwarding state and not pruned

-------- ---------------------------------------------------------------------

1/1 1-2,4,6-7,13,15-16,20,23-27,33,153,209,224,254

CAT6509 (enable) show trunk 5/3

* - indicates vtp domain mismatch

Port Mode Encapsulation Status Native vlan

-------- ----------- ------------- ------------ -----------

5/3 on dot1q trunking 1

Port Vlans allowed on trunk

-------- ---------------------------------------------------------------------

5/3 1-1005,1025-4094

Port Vlans allowed and active in management domain

-------- ---------------------------------------------------------------------

5/3 1-2,4,6-7,13,15-16,20,23-27,33,153,209,224,254

Port Vlans in spanning tree forwarding state and not pruned

-------- ---------------------------------------------------------------------

5/3 1-2,4,6-7,13,15-16,20,23-27,33,153,209,224,254

glen.grant · ‎11-09-2007

What code version are you running on the 4006 . this sounds like a old bug that was prevalent back in the 5.X train to the mid 6.X train where users in the vlan could not talk to each other . We did see this problem in our large install of the 4006's . Have not had a problem since we have been in the 7.X train . If your code is old you might want to upgrade as your problem sounds like a code bug that was prevalent , i would post the bug number but the bug toolkit seems to be down more than its up lately.

ddemirchi · ‎11-10-2007

cat4xx

show run 1

Cat 65xx

show run 5

Since you are running dot1q, have you defined native vlan?

and

set port dot1q-all-tagged 1/x enable

---

and have you tried ISL for testing?

Cat4x

set trunk 1/1 on isl 1-1005,1025-4094

Cat65x

set trunk 5/1 on isl 1-1005,1025-4094