Moving IPs from one VLAN to another

[enelson11]

You'd think this would be easy. I have two switches in HSRP and VLANs that need to get re-numbered.

VLAN1->VLAN101 

VLAN2->VLAN102

ect

I have a few VM hosts on these VLANs and the tags have been added to those systems. Each time I attempt to just move them with the following script;

interface Vlan4
no ip address 10.119.4.1 255.255.254.0
no standby version 2
no standby 4 ip 10.119.4.5
no standby 4 priority 200
no standby 4 preempt

interface Vlan104
ip address 10.119.4.1 255.255.254.0
standby version 2
standby 4 ip 10.119.4.5
standby 4 priority 200
standby 4 preempt

It breaks my services. I put things back, it's all back to normal right away. The other half of the HSRP setup is the same, just different host IP and priority. I shouldn't have to clear ARP or anything for this, do I? Am I getting burned by Span-Tree?

[Meheretab Mengistu]

Hi,

I am confused.

The other half of the HSRP setup is the same, just different host IP and priority. Did you apply the change to both switches at the same time?

Have you created the new vlans on the switches? 

Once you added the SVI (interface vlan104), is it in UP/UP state?

[enelson11]

Yes, the changes where made to both switches at the same time. VL10X are all up and applied to all trunk ports. The VLANs are up/up. The L3 routing occurs on the switch I am making my changes at. I am able to ping the IP after I move them to the new VLAN from connected switches, but VMs all fail connectivity. All VM hosts have the new VLANs added to the trunk link and to their virtual switches.

[Daniele Giordano]

I don't know the reason. Should be investigated with more details.

I want suggest a workaround:

1) you can download the startup config using tftp (copy startup-config tftp)

2) edit the configuration using notepad and change vlan id and interface vlan id

3) load the new version to the swith using tftp (copy tftp startup-config)

4) check the config using show startup-config

5) if all seems ok try to load the configuration using copy startup-config running-config or simply reboot the device if you can

This workaround can make the switch unavailable, so check if it's a possible solution and check if you have a console access to device.

[enelson11]

The good thing is that this is in my disaster recovery site and downtime shouldn't be an issue. I'm going to try that since I'm at a loss. My lab populated everything just fine and right away. Guess I'll use this as a good time to update code. Maybe that has something to do with it.

As to your other reply, I have not cleared the ARP. As it worked on my lab, I didn't think to try that. I think I'll move forward with the code upgrade and restart anyways as this just makes it a two for one change I can clear out. Who says doing two changes at once is a bad thing?

[Reza Sharifi]

After building the new vlan (104) when you do a "sh ip arp vlan4" do you see the VM hosts IPs still associated with this vlan? If yes, you may want to clear the arp cash and try again?

Also, does HSRP work fine for vlan 104?

HTH