3Com 4200 28-port VLAN creation problem - HELP!

[scornflake]

I have 2 3Com 4200 28-port switches (Product #: 3C17304A) on which I'm trying to set up a few VLANS. I've outlined what, exactly, I need to do here:

http://www.scornflake.com/examples/network.jpg

Basicly, my problem is that when I create, say vlan2 first, assign the ports to it, and connect the fiber, it works. When I add vlan 4 and it's respective ports, and connect the second fiber, it stops working. I wouldn't say it's looping as you'd expect if you just connected two redundant links at the same time without aggregation, but the second vlan is definitely not working. I've had it suggested that because the fiber links are only connecting the switches, that I need to make those ports something other than plain-old untagged member ports, as I've made the other 100mb ports in the vlan.

I'm just spewing all this out to try to get some dialog going, I'll be happy to provide any additional info I may have missed.

Thank you for any assistance you can provide.

 

[SYQUEST]

What happened to VLAN1? According to the documentation, if you assign everything away from VLAN1 you loose web access don't you?

Why 2 fiber and one copper between the switches? One of the benefits of fiber is bandwidth. So why not use one and do trunking for all the VLANs?

....JIM....

 

[scornflake]

Yes, you're correct, I didn't assign ports 1 or 13, so it's still admin-able through those ports.

Good idea on the trunking, I didn't know that much about it when I started this, and it makes sense to do that, although I'm wondering, if I want to enable the trunking, and run all 3 vlans on one fiber, so I need to make the fiber ports "tagged" to allow more than one vlan to use them? if so, then I need to include that port (say, port 27)in each of the vlans? also, if I make them tagged ports, do I need to do anything else to allow it to work? I thought I had read that untagged packets (traffic from ports that are untagged) will be dropped if sent to a tagged port (the fiber) is this not correct?

Basically, I'm pretty unskilled at this so far, is all I have to do set the fiber ports to "tagged" and include that pot in each of the vlans?

Thanks for the continued assistance.

 

[SYQUEST]

Well that makes two of us. I am learning about VLANs also. Reading does help, but 3COM's docs are not as detailed as Cisco's. My client's setup calls for a VLAN between a 3C16475BS and a C2950G-24EI using GBICs.

I got some basics that I will attempt to use to configure the VLAN this week.

....JIM....

 

[SYQUEST]

Hi Scornflake,

I did get the VLAN to work, although I still have one minor problem. Since the VLAN did not have continuity when I powered the switch once it was installed. I had to remove it then add it back on the 3COM. Then it worked!

What I was going to suggest to you, try setting the fiber in the VLAN as UPLINK 'U' not 'D' and see if that works for your VLANs. Start simple and go from there.

If it appears to be to much for one fiber, setup the 2nd one and put the 3rd VLAN on it.

Hope this helps!

....JIM....