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VLAN ID change and problems afterward

jeremy-rogers
Beginner
Beginner

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?


1 Accepted Solution

Accepted Solutions

JulieMcP
Cisco Employee
Cisco Employee

Hi, Jeremy,

I recommend you also post this question to the Cisco Support Community for additional information and feedback: https://supportforums.cisco.com/

I hope this helps. Thank you for participating in the community.

Julie

View solution in original post

3 Replies 3

Fraydoon Razazi
Beginner
Beginner

Did you define the new VLANs on the access switches? Did you also modify the Port-channels on access switches?

Yes to both

JulieMcP
Cisco Employee
Cisco Employee

Hi, Jeremy,

I recommend you also post this question to the Cisco Support Community for additional information and feedback: https://supportforums.cisco.com/

I hope this helps. Thank you for participating in the community.

Julie

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