I have a question pertaining to switching and VLANs.
Our current setup at work is a core HP procurve switch that is broken into 4 vlans. We have lab, corp, user and server. We just expanded offices and now we have a need for a switch in the new lab (about 200ft) away.
I am connecting the switches (Cisco 3500XL to HP procurve) via a straight through (should be a CO I know, but one of the switches is taking care of switching the wires for us) and have only ran a single line. When I plug into the switch I am assigned an address in whatever vlan I am in on the switch (all good). So it looks like this:
HP Procurve (cable plugged in lab)-> Cisco 3500 (cable plugged in anywhere) -> Me (assigned a lab address)
There has been no configuration to the swtich so I am kind of confused how the switch knows to just send the data across the line when the port I plugged into has no vlan information and I have no trunk configured. So my first question is how does it do this?
My second questions gets more detailed. Lets say I run another line to the switch. This time the line is plugged into corporate. I do not want lab and corporate to talk. When I plug the laptop in it gets assigned whatever dhcp comes back first.
This is not practical and I know there has to be a more granular way to control this. If I had a 2 ciscos switches, I could just use VTP and transmit the vlan information, but in this case, being its an HP and Cisco, I can't.
My idea was to run the lines from the HP to the Cisco switch. From there I would configure them as trunk lines between eachother. I would configure the Cisco switch to have a trunk for the lab vlan and a trunk for the corporate vlan and then configure each port for vlan. So when a lab user wanted to access a lab node their packet would be tagged, sent to the proper trunk, sent over the trunk and then handeled at the HP. I think something like this would work, but if not could someone point out why? Also would trunking have to be configured on both ends (HP and Cisco)? And if this wouldn't work, does anyone have an idea what would?
If anyone has any ideas they would be greatly appreciated. Also, if you have any insight to what I have said so far then please feel free to comment. I understand this stuff, but sometimes confuse myself.