I can not connect trunking Catalyst 4006 and AT8324SX Allied Telesyn

[hungnm]

Hi all,

I can not connect trunking between Catalyst 4006 and AT8324SX Allied Telesyn by 802.1q. Pls help me solve this problem, below is my configuration:

!

interface FastEthernet2/34

switchport trunk encapsulation dot1q

switchport mode trunk

duplex full

no snmp trap link-status

!

and below is sh command:

APV4006#sh int trunk

Port Mode Encapsulation Status Native vlan

Fa2/34 on 802.1q trunking 1

Port Vlans allowed on trunk

Fa2/34 1-1005

Port Vlans allowed and active in management domain

Fa2/34 1-4,7,1002-1005

Port Vlans in spanning tree forwarding state and not pruned

Fa2/34 1-4,7,1002-1005

FAPV4006#sh int fa2/34 switchport

Name: Fa2/34

Switchport: Enabled

Administrative Mode: trunk

Operational Mode: trunk

Administrative Trunking Encapsulation: dot1q

Operational Trunking Encapsulation: dot1q

Negotiation of Trunking: On

Access Mode VLAN: 1 (default)

Trunking Native Mode VLAN: 1 (default)

Administrative private-vlan host-association: none

Administrative private-vlan mapping: none

Operational private-vlan: none

Trunking VLANs Enabled: ALL

Pruning VLANs Enabled: 2-1001

FAPV4006#sh vlan

VLAN Name Status Ports

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

1 default active Gi1/1, Gi1/2, Fa2/33

2 VLAN2 active Fa2/29, Fa2/30, Fa2/31, Fa2/35

3 VLAN3 active Fa2/1, Fa2/2, Fa2/3, Fa2/4

Fa2/5, Fa2/6, Fa2/7, Fa2/8

Fa2/9, Fa2/10, Fa2/11, Fa2/12

Fa2/13, Fa2/14, Fa2/15, Fa2/16

Fa2/17, Fa2/18, Fa2/19, Fa2/20

Fa2/21, Fa2/22, Fa2/23

4 VLAN4 active Fa2/24, Fa2/25, Fa2/26, Fa2/27

Fa2/28, Fa2/36

7 VLAN7 active Fa2/32

1002 fddi-default active

1003 token-ring-default active

1004 fddinet-default active

1005 trnet-default active

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

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

1 enet 100001 1500 - - - - - 0 0

2 enet 100002 1500 - - - - - 0 0

3 enet 100003 1500 - - - - - 0 0

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

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

4 enet 100004 1500 - - - - - 0 0

7 enet 100007 1500 - - - - - 0 0

1002 fddi 101002 1500 - - - - - 0 0

1003 tr 101003 1500 - - - - - 0 0

1004 fdnet 101004 1500 - - - ieee - 0 0

1005 trnet 101005 1500 - - - ibm - 0 0

Primary Secondary Type Ports

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

Thank you very much

Hung

[milan.kulik]

I don't know Allied Telesyn configuration.

But generally while 802.1q trunking to other vendor switch there might be two basic problems:

1) Negotiation of Trunking: On in your Cisco config - the other side might not support trunk negotiation, try to change to "no negotiation"

2) native VLAN1 - the other side might not support native VLAN (untagged frames) feature on 802.1q trunk. There is "dot1q-all-tagged" possibility in CatOS and there should be something similar in IOS (I don't remember the exact command).

Regards,

Milan

[raarons]

If memory serves, the AT switches tag all vlans, point 2 is correct.

Another way to get the trunking working is to set the native vlan on the Catalyst to some unused number. You don't say whether the 4006 has a Supervisor II or III in it, so it might be running CatOS or IOS. If the unused vlan is 999...

- on SupII

set vlan 999 x/y

- on SupIII

int x/y.999

encapsulation dot1q 999 native

HTH