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Stealing ip addresses from one Vlan to another Vlan

ITmike
Level 1
Level 1

I have a switch that has several Vlan's set up on it.

One of the Vlan's does not touch our network and I need to take 2 ip addresses from that Vlan and put them on another Vlan in the same switch.

 

Vlan20 - 192.168.1.1 - 192.168.1.255

Vlan30 - I would like 192.168.1.200 - 192.168.1.202

 

The DHCP server is not on this switch, but another one at our corporate office, which I do not have access to.

 

How do I do this?

6 Replies 6

Reza Sharifi
Hall of Fame
Hall of Fame

Vlan 30 is most likely in a different subnet. So, you can't take the IPs from vlan 20 and assign them to 30.

The easiest way to configure 2 ports in vlan 20 and assign the 2 IPs to it and make sure it is excluded from the DHCP scope.

HTH

Well I was thinking something like this



interface Vlan20

ip address 172.18.20.1 255.255.255.0

ip dhcp exclude-address 172.18.20.200 172.18.20.202

!

interface Vlan30

ip address 172.18.20.200 255.255.255.252





Not sure if that will work, but I think it will.



That way I can put one of my 10 access points on vlan 30 for the 2 systems I need those ip addresses for.


interface Vlan20

ip address 172.18.20.1 255.255.255.0

ip dhcp exclude-address 172.18.20.200 172.18.20.202

!

interface Vlan30

ip address 172.18.20.200 255.255.255.252

 

This config will not work as 172.18.20.200/30 subnet is already part of /24 subnet (172.18.20.1 255.255.255.0)

HTH

Yea I was afraid of that.

 

will have to try your first suggestion.

 

Thanks

 

The easiest way to configure 2 ports in vlan 20 and assign the 2 IPs to it and make sure it is excluded from the DHCP scope.

so I have one AP to one port, so can I assign an Ip scope to that port?

 

 

Vlan 30 is most likely in a different subnet. So, you can't take the IPs from vlan 20 and assign them to 30 - how would I do this without an exclusion on vlan 20?

The configuration on this port is the following
interface GigabitEthernet1/0/28
description WAP NW
switchport trunk native vlan 40
switchport trunk allowed vlan 1,5,20,40
switchport mode trunk
!
Vlan 40 is a separate ip addresses structure that is on our network, so I can't use it, and it is only for the AP's.
The port is trunked as needed by the AP.....so how do I assign 2 ip addresses to it?
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