topic Re: Basic 2848 VLAN Configuration question in Switches, Hubs, and Modems

Basic 2848 VLAN Configuration question

Andrew Gillies — Thu, 16 Jul 2009 12:45:34 GMT

Good Day,
Hopefully simple VLAN configuration creation:

Quick background: Would like to integrate VLANS into LAN. Up until now, we have had 2 flat networks physically separated off of router. Unfortunately no experience with VLAN configuration, so would like to keep setup simple to start and as understanding of VLANs grow, incorporate more down the road.

We have a new 2848 with default settings.
Would like to have 2 VLANS on this switch.
#1 VLAN Ports 1-46
#2 VLAN Port 47
Both VLANS would connect to DHCP/Internet/Router via port 48
#1 VLAN can access VLAN #2
#2 VLAN cannot access #1 VLAN

We will have one side of our network branch off port #1 and the other side branch off port #48. Will the switches that branch off this 2848 switch need to be configured with VLAN information also? (Almost all of our equipment is 2848s and 2824s).

As a side question, is it possible to have VLAN#2 receive separate ip addresses? Ideally #1VLAN will have 10.2.1.0/16 and #2 VLAN will have 10.3.1.0/16.

Thank you very much for any insight that can be provided!!
Andrew

Re: Basic 2848 VLAN Configuration question

Andrew Gillies — Thu, 16 Jul 2009 13:00:24 GMT

Minor Typo:

Meant to say:
We will have one side of our network branch off port #1 and the other side branch off port #47. Will the switches that branch off this 2848 switch need to be configured with VLAN information also? (Almost all of our equipment is 2848s and 2824s).

:-)

Re: Basic 2848 VLAN Configuration question

Pieter 't Hart — Fri, 17 Jul 2009 14:10:56 GMT

>>>
Will the switches that branch off this 2848 switch need to be configured with VLAN information also
<<<
basically NO
if you configure Port 47 to the other switch as "untagged" #2 VLAN, vlan information is stripped from packets sent to the branch and passed by that switch in the only vlan it knows (vlan1)
but you'll miss some advantages of vlan's

>>>
Both VLANS would connect to DHCP/Internet/Router via port 48
<<<
you router must also understand vlan's on a single physical port, and match the tagged/untagged config of the switchport