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VLAN ID change and problems afterward

Question asked by jeremy-rogers on Jan 3, 2017
Latest reply on Jan 4, 2017 by julmcphe

I have 4 vlans currently, 100,200,300,400. I have 2 offices and they both used the same numbers, but now I need to change on office because of a DR system that we are putting in. I need to change one office to VLANs 111-114. I understand that I can't just change the number. I have to create these new vlans and move the associated IP addresses. Here is what I did.

 

I created the new vlans

config t

int vlan 111

int vlan 112

int vlan 113

int vlan 114

 

remove the IP from the old vlans

int vlan 100

no ip address

int vlan 200

no ip address

int vlan 300

no ip address

int vlan 400

no ip address

 

add the ip to the new vlan

int vlan 111

ip address 192.168.1.1 255.255.255.0

ip helper-address 192.168.1.20

int vlan 112

ip address 192.168.2.1 255.255.255.0

ip helper-address 192.168.1.20

int vlan 113

ip address 192.168.3.1 255.255.255.0

ip helper-address 192.168.1.20

int vlan 114

ip address 192.168.4.1 255.255.255.0

ip helper-address 192.168.1.20


Then I change the DHCP server (192.168.1.20) to use the new VLAN numbers. Then I change the Port channels to the access switches to the new vlan ids. Then the access ports on those switches. I then flushed the arp cache.


Here is the problem. All routing seems to be broken now. I can pull and IP from the DHCP server on the vlan 111 only. From the DHCP server I can ping 192.168.1.1, but not 192.168.2.1 or any of the other vlan ips.


What did I do wrong? Was I suppose to flush the MAC address table? Was I suppose to shutdown the old VLAN ids?


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