Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

how to create 2 vlan with one port connected to both.

how to create 2 vlan with one port connected to both.

how to create 2 vlan with one port connected to both.



my setup is default vlan with all ports untagged. I need to create a second vlan (vlan2) and add 6 ports to it. but i need 1 port that can access both vlans.

default vlan
switch is 5406zl

 Do i need to enable ip routing?

I have the vlan2 setup with 1 port tagged.

 any help is much appreciated!



RE: how to create 2 vlan with one port connected to both.

You will have to give more details.
A switchport can carry as many VLANs as you desire (well, there are limits) - it will have one VLAN "untagged", and you add as many more as you need as "tagged".
If you need devices on one VLAN to communicate with device that are on another VLAN, you will need a router (or layer3 switch, eg your 5406) to do it.
If you have a host that has virtual interfaces in two subnets, then you configure its physical interface to use 802.1q with both VLANs configured on it, then patch that into a switchport that is also configured for those two VLANs.
As I said, more details on what you're trying to do.

RE: how to create 2 vlan with one port connected to both.

In simple terms, using the untag command in your config will cause those ports to be dedicated to that VLAN. Using the tag command will cause that VLAN to flow down that port.

So for example, when you show config:

vlan 1
 untagged A1-A24
 no untagged B1-B24
vlan 2
 untagged B1-B24
 tagged C1

So ports A1-A2 are in one VLAN, while ports B1-B24 are in another VLAN. The two VLAN are operating at layer 2, so think of each group of ports are two logically different switches. When you put an IP address assignment to them:

vlan 1
 untagged A1-A24
 no untagged B1-B24
 ip address
vlan 2
 untagged B1-B24
 ip address
 tagged C1

It now becomes a layer 3 interface. When you add the command
ip routing
your VLANs will now "talk" (route) to each other (they won't otherwise).

The C1 port used in this example is connecting to another VLAN aware switch. The VLANs being pushed down this wire will be the default VLAN 1 (it's the default VLAN on all switches, so that's why you don't see a tagged command under that interface) and VLAN 2. If you had another VLAN defined, say VLAN 3...as long as I tag C1 under the VLAN 3 interface, then that VLAN will also get pushed down the wire. If you are connecting another switch to the C1 port on the 5400, then you will basically do the same type of config on the other switch, making sure you define the same VLANs and tagging the port used for uplink back to the 5400. Once done, you can divy out ports on that other switch to VLAN 1 or VLAN 2, etc... by untagging them under the VLAN's interface.

Hope that helps.


Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members! Already a Member? Login

Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close