Unanswered Question
Sep 12th, 2007
User Badges:

Hi, I need to know if two host PCs which are part of the same subnet but are in different VLANs can ping each other if the hosts are connected to two different switches. The switches are also connected by two access ports and those ports are assigned to different VLANs as well. The configuration is described below.

SWA`s FA0/1 is assigned to VLAN 2 in which PCA resides and its Gi0/1 is assigned to VLAN 2 and attached to SWB.

For SWB, Fa0/1 is assigned to VLAN 3 in which PCB resides and Gi0/1 is assigned to VLAN 3 and connected to Gi0/1 port of SWA.

Best regards.

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (1 ratings)
onurcoskun Wed, 09/12/2007 - 06:51
User Badges:

Well I`ll try to make myself more articulate. Are ports (switchport modes are access btw), which connects two switches together, allowed to be assigned to different VLANs?

Thanks again.

paul.matthews Wed, 09/12/2007 - 07:08
User Badges:
  • Silver, 250 points or more

When all are set as access ports, there is no tagging of VLANs. The two ports of interest are in the same VLAN (2) on switch A, so traffic can flow. Similarly on switch B both interested ports are in VLAN 3, so the PC *should* be able to talk, however this is rather a silly configuration and if it got beyound two switches it would be difficult to support as you would need to maintain VLAN translation tables alongside your normal documentation - ie

Switch A Switch B


I really hope this is an academic consideration to help understand VLANs...

onurcoskun Wed, 09/12/2007 - 08:47
User Badges:

This has been an acacademic consideration to understatand VLANs and it solved the questions on my mind. Thank you.

paul.matthews Wed, 09/12/2007 - 23:34
User Badges:
  • Silver, 250 points or more

No problem - I just sometimes get a little wary when people are asking things that would not be wise to do in a live network just in case they take me saying it will work as advice that it is agood thing to do!

Please remember to rate all helpful posts,



This Discussion