How to configure trunk/vlan 3Com 4250T and 4500?

Question

Network administration

There are 3x3COM 4500 and 3x3COM 4250T, 3 VLANs (1,2,3) are configured on 3x 4500
1 VLAN 5-50 untagged
2 VLAN 1-2 untagged (49 50 tagged, TRUNK)
3 VLAN 3-4 untagged (49 50 tagged, TRUNK)
Now there is a need to plug in another 3x3COM 4250T and connect them through port 49, 50.
This action completed "successfully", the packets go through all switches (VLAN 1), but when assigned to port 2-3 VLAN'a, nothing is pinged.
I saw AL1-AL4 in the settings, what is it?
What could be the problem?
When adding 1-24 ports on any switch 4500, 2 VLANs work, with the same command on 4250T, packets go nowhere ...
addport vlan 2 1:1-1:24 untagged

Answer 1

It's decided.
On 2x 4500, there was access access on ports 49 and 50 on the first and third, respectively, after changing to trunk everything worked, on 4250T with native firmware there is no trunk at all, but it picks up all packets. The only disadvantage is that devices from these switches do not see devices in other switches on the same VLANs.
(although inside the switch everything is visible and pinged)