1

I was configuring a pair of HP ProCurve 2530 switches last night and was created VLAN's. I created 4 VLAN's that I'm going to tag for port 24 where the switches will connect to each other. However, I'm a little confused.

On port 24, I went ahead and noted the VLAN's as tagged. Once I did that and the switches were connected, they could ping each other just fine through the IP's I had given them on those VLAN's (for example 10.100.0.2 and 10.100.0.3).

In the port configuration, I can put a port in a trunk group (for example, trnk1) and then go to the VLAN page where I can mark the VLAN's as tagged for the trunk (at this point, port 24 is missing, with trnk1 in its place). Pinging still works as expected when I do it this way also.

So what's the difference? Can traffic from a device on one switch to the second switch only pass when it's trunked? I don't have any devices yet plugged into these switches to really to test this.

What's the difference between just tagging the port versus tagging the trunk port I created from port 24 in my example?

Sokel
  • 291
  • 2
  • 6

1 Answers1

1

Terminology is confusing here. The trunk you created has nothing to do with VLANs. Rather, it's a link aggregation mechanism to bond multiple physical circuits into one trunk. This functionality is referred to by different names: trunk, LAG, EtherChannel, etc.

So, yes, VLAN tags will happily transit a trunk port, just as they will a single standalone port.

So boil this down, you don't need a trunk here unless you are planning on needing to use multiple physical links between switches.

EEAA
  • 109,363
  • 18
  • 175
  • 245
  • Erm...a trunk can mean any number of physical links carrying multiple vlans - I think that was the intention here – Chopper3 Sep 28 '16 at 21:01
  • @Chopper3 Right. The trunk is not required in this case, though. Many people hear "VLAN Trunks" and then they see "trunk" in the switch configuration and think it's required, when it's not. Hence the confusion. – EEAA Sep 28 '16 at 21:05