3Com 3870 switch Config

ok to work down 1 fibre:
Assigned ports 1-12, & 24 to Vlan 1 (Tagging 24) - 192 network
Assigned ports 13-22 & 24 to Vlan 2 (Tagging 24) - 172 network.
Port 24 then connects via fibre to a second switch configured in the same way. This works fine!
Then I would assign port 23 to Vlan 2 and remove port 24 from vlan 2. (First tried tagging 23 & 24 and then untagged). This is where the problems start. I have tried assigning IP's to the Vlans and even adding an ACL but still the switches fail to work with 2 uplinks!
The new 3Com switches (4500s) have the option to configure the ports as TRUNK or ACCESS but these 3870's don't. Well not that I can find either via the CLI or the web access.
I Know I have done this before and I am sure I never went through all this but I just can't seem to get it this time.... It is driving me mad!

So old 3com switches names TRUNKs as "Tagging". I guess it's either 802.1Q or VLT.

Any way, Removing all tagging (trunking) from ports 23 and 24 and assigning port 24 to VLAN1 and port 23 to VLAN2 just as normal ports, then connect port 24 to an ACCESS VLAN1 port on the 4500, and connect port 23 to an ACCESS VLAN2 port on the 4500s, this should work. It's strange that it didn't!!.

Try this just for testing. Disconnect both 23 and 24. Then connect port 12 to a VLAN1 port on the 4500. And connect port 22 to a VLAN2 port on the 4500. If this works, then your problem is somewhere in the ports 23 and 24 configuration.

p.s. You know you need crossover cables between switches off-course.

Thanks for your help, I have a working solution now, not quite what i originally wanted but it will work until i have a better understanding of the switch's.

Thanks again for your help

Great, So what was the solution?

Since your using 2 uplinks here. You don't need to set them as TRUNK ports any more. Just set both as ACCESS mode each one as part of it's corresponding VLAN, it should work this way.

if you set both as access how about intervlan communication

any way, i am suspecting the introduction of a router with multiple fastethernet interface will help- a layer three device is needed.