vlan between a cisco 6509 and a 3com 3300

[joysa]

I need help configuring a vlan between a 6509 and a 3300. I created the vlans in the 3300 and 6509 and assigned ports to them. In the 3300, do I have to place the port used for the link as a member of each vlan? Do I have to enable 802.1q vlan learning?. It seems that trunking means different things for cisco and 3com. Any help will be appreciated.

Thanks

 

[jeter]

You do need to setup a trunk between the switches.
check out these sites for a better understanding.

http://www.cisco.com/warp/public/473/21.html

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat5000/rel_6_1/config/e_trunk.htm#10497

Jeter@LasVegas.com
J.Fisher CCNA

 

[thenetwraith]

Cisco's support 3 "Trunking" protocols, depending on switch and version. These are: ISL, 802.10 and 802.1q.

ISL is Cisco proprietary, so ....

802.10 is also called SDE (Secure Data Exchange) mostly used for FDDI, but, I think it can go elsewhere. The 3-com just may support this, but, it's an older protcol, so ....

802.1q is the most recent and standard. If the 3-COM has 802.1q then you have a chance. A couple of tips to help:

1) Keep the management IP's on the same subnet and use the default VLAN for management. (Some switches will automatically default this when the switch resets).

2) Experiment with the default and one other VLAN. My experience with 802.1q is that it takes a bit of time to converge and doesn't always behave the way you would think it should. Keeping it simple should help you work it out.

3) You might consider trunking through a third switch with a 'probe' port and setting up a system or sniffer to capture packets between the trunk members. It's the best way to get a clue as to what is really happening. Don't turn the trunking on through the probe switch, just let it pass the packets transparently (If it can -- but layer 2 should be able to anyway..)

4) Since trunking implies tagging, you may need to experiment with STP (Spanning tree protocol). Tagging is the operation of appending a VLAN tag to a packet that needs to transverse a trunk. The recieving switch will strip the tag before sending it to a non-trunked port destination. The RUB here is: Since this works on the ARP level and requires a layer-2 learning function (Simple ARP doesn't work since you have multiple pipes), Spanning tree may NEED to be enabled. This depends on whether the switch has separated these functions from the Spanning tree. BEWARE: If either of the switches support bridge groups, the spanning tree will behave differently. (The 6509 does for sure...)

5) If all the above makes you think: "What a mess!!", then : I welcome you to the world of VLAN trunking! , Enjoy the adventure....


Reply-to: netwraith@pcrd.net
thenetwraith (There is a picture here, but, you just can't see it!)

 

[wybnormal]

Also, keep in mind that "trunking" for cisco does NOT mean the same thing in the 3com world. 3com's web site has several papers about hooking 3com to cisco equipment. I posted a few link under the 3com forum.. somewhere ... I dont remember exactly where but given they are not bursting with activity, it should be easy to find.

Your only choice that I am aware of with 3com is 802.1Q But they something called "open and closed" vlans. If I remember right, you need to use *open* VLANs.

Good luck

MikeS "Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin

 

[10496]

Yes, in the 3300, you have to place the port used for the uplink as a member of each vlan? And in 3300 I believe there is something like 802.1q tagging which you need to do when creating the Vlans. Be careful about the term trunking - it has differrent meaning in 3Com !