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New Member

simple vlan interface question

I setup two additional vlans on a new switch, trunked to existing network switches and enabled VTP. All switches now see the other vlans. I tested with a server which works on vlan 1 but as soon as I move it to another vlan, it can't even ping the switch. I am guessing this is becuase the switch interface is set up as vlan 1. So, my question is, can I use the same ip address for vlan 2 and 3? If so, do I just use the int vlan2 command and assign the same ip address? If not, I'll assume, I need to use the int vlan2 command and assign a different address in the same subnet. Please advise...


Re: simple vlan interface question

In order to route between the vlans ( going from vlan 2 ----> vlan 1 ) , you need an ip address on interface vlan 2 that is different from vlan 1 ip address . You cannot use the same ip addres for 2 different vlans. Keep in mind you will also have to readdress your clients beside just adding the vlan interface ip .


Salman Z.

New Member

Re: simple vlan interface question

The existing network has never been vlanned. We now have blade servers in an enclosure with a switch attached.I have 4 servers on the switch in the enclosure that are trunked to a switch to an app server farm in subnet 192.168.168.X.

The other 4 servers are trunked to a switch in the web server farm in subnet 192.168.252.X.

vlan 1 (native) has an ip address What is the best way to divide and conquer here? Can I leave the native as is, so I don'thave to change all the switch ports on the existing app server farm (subnet 192.168.168.x)?

Then I only need to create vlan 2 to the other subnet (192.168.252.x). In this case, all the other existing servers on the existing switches will have to be assigned to vlan 2. Am I thinking logically here?

New Member

Re: simple vlan interface question

I have a couple of suggestions:

> verify that the vlans are being setup on the VTP domain server and not a VTP client/transparent.

> verify that the all switches (except the VTP server) are in client mode so that they may pickup the VLAN changes.

> verify that the vlans being trunked are allowed.

> keep in mind that VLAN's can be defined per port where trunking is concerned. You can have subnet 192.168.252.x on port 1 and subnet 192.168.222.x on port 2.

> not sure which switch you are using but the {int range} command if available is awesome for changing many ports at one time.

hope any of this helps.

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