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catalyst 6500 series 6506


Could someone advise on how to configure/setup/command multiple vlans tag and untag on this switch 6500.

Eg: vlan 30-35 to module 3/2-3

I couldn't find any doc on the web. Thanks.


Re: catalyst 6500 series 6506

Just go to and search on configuring trunking , there is a ton of docs on how to do this across all the switch types...


Re: catalyst 6500 series 6506


From your post it sounds you may be using hybrid. If so the intended task is configured in CatOS. You can use the "set vlan" command from "console(enable)" prompt. E.g. your example would read: "set vlan 30-35 3/2-3".

Best regards,


New Member

Re: catalyst 6500 series 6506

Thanks Antonin. Will the set command set to tagged vlan?. Are there ways to configure multiple vlan to a single ports; this I think can achieve with different switch than the 6500. It's really pain to configure the 6505.


Re: catalyst 6500 series 6506


My "quick and dirty" rules as for the tagging/untagging packets are as follows:

1) General rule with Cisco equipment: packets belonging to vlans are tagged within trunk only.

2) basically we can specify 2 types of ports - let us call them trunk and access,

3) trunking can be negotiated, ie. port specified as trunk may or may not become a trunk at the end,

4) Cisco equipment may support 2 types of trunk: ISL (Cisco proprietary) and dot1q (802.1Q standard),

5) trunk ports carry tagged packets,

6) native vlan within dot1q trunk may or may not be tagged (configurable),

7) access ports are access ports, ie. cannot become a trunk and packets leaving these ports are not tagged, also packets coming to these ports are expected to be untagged,

8) access ports may belong to one vlan only,

9) things may be further complicated with EtherChannels,

10) There are few exceptions to these rules which I am not going to cover (e.g.

historically some Cisco equipment also supported so called multi-vlan ports, with voice support you specify "auxiliary" vlan etc.).

To answer your question:

You cannot configure a single port to carry untagged packets which would belong to multiple vlans, the only way to support multiple vlans per port is trunk.

Further comments:

- If you have hybrid it may seem pain to configure Cat6505 but in my view moving to native we lose quite a few features.

- I may confused you in my previous post by my example, which I put for simplification. The actual commands can read "set vlan 30 3/2-3", "set vlan 31 3/4", set vlan 33 3/8-10" etc. NOT multiple vlans per port - sorry about that.

- to set trunk ports there is the a CatOS command "set trunk".

- I hope my English makes sense.

Best regards,


New Member

Re: catalyst 6500 series 6506

Thanks. Here is the brief config.

xxxx> (enable) show trunk

* - indicates vtp domain mismatch

# - indicates dot1q-all-tagged enabled on the port

Port Mode Encapsulation Status Native vlan

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

6/31 on dot1q trunking 83

Port Vlans allowed on trunk

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

6/31 1,80-91

Port Vlans in spanning tree forwarding state and not pruned

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

6/31 1,80-91,


Show running config section


#module 6 : 48-port 10/100/1000BaseT Ethernet

1) set vlan 83 6/21-23,6/31-32

2) set trunk 6/31 on dot1q 1-1005,1025-4094

I can't still can't not ping the 83 network. I know it will work if line #2 is set to this:

set trunk 6/31 on dot1q 83, 1-1005,1025-4094

I did used the command set trunk, but it's not show 83 in the above line.


Re: catalyst 6500 series 6506


I am not quite sure I fully understand your post.

From part of your configuration for module 6 I can see that you have set up the port 6/31 as trunking unconditionally (mode "on") and also you have changed the native vlan from default to vlan 83 which is confirmed by the "show trunk?" output. Your connectivity problem ("83 network") may be due to the fact that this side is trunking while other side not (that is the danger of setting the mode to "on") or perhaps there is a native vlan mismatch (have you set up other side for vlan 83 as well?).

Please do not expect to see "set trunk 6/31 on dot1q 83,1-1003,1025-4094" line in your configuration as vlan 83 is part of 1-1003 range (even if you issue "set trunk" command which would list vlan 83 separately in addition to the whole range).

What I am totally confused about is this part of your post: "I know it will work if line #2 is set to this: set trunk 6/31 on dot1q 83, 1-1005,1025-4094". Will you please let me know what makes you think so.

Thanks & Regards,


New Member

Re: catalyst 6500 series 6506

Thanks Amikat. Today I removed the vlan 83 by setting 6/31 to vlan1. I then cleared the trunk port and set the trunk again. It's working now. Sorry about the confusion since I am still a newbie and learning. Also thanks for your explanation about the tag and untag.

You know as to other switches like smc, foundry, etc... you can use the key work remove, tag, and untag, etc... As for the cisco, I quite understand now, but would like to confirm with you again: so the way to "tag" vlans in a cisco env is "trunking" right? if no "trunking" is used then it's untag right?

As for LACP, I was told that LACP only work if let say 2x or 4x ports are in a consecutive order right?

Eg: port 1,2 will work for LACP right?

Eg: port 1,2,3 will work on 2x porst only right? since it's odd number?

Eg: port 1,2,3,4 will work right?

Is lacp base on the physical ports? I mean you have to the port sitting next to one another right? eg: ports 4,5,6,7. If that the case then it's not very friendly then because you cannot virtually (let say) lacp ports 4,5,6,20?

By working on this I some how understand more in term of the concept.


New Member

Re: catalyst 6500 series 6506

Thanks Glen.

Cisco Employee

Re: catalyst 6500 series 6506

Hi Friend,

If you want multiple vlans to be on same port then you need to configure trunking.

Check this link and it will give you commands to perform your job



New Member

Re: catalyst 6500 series 6506

Thanks Ankur

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