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Deleted vlan.dat from flash

I have an 871 router I am redeploying. I did a factory reset on it and just to make sure it was clean I deleted the vlan.dat file from flash. I reconfigured the router and noticed DHCP is not working. DHCP seems to be fine but when I look in flash there is no vlan.dat file. I expected it to be recreated with I re-created my VLAN. Is there a way to recreate this?

Cisco Employee

Re: Deleted vlan.dat from flash

Hello Harrison,

The vlan.dat file should be created on the fly when the router deems it necessary. This might be related to your problems with DHCP but it is not the only possible reason.

The vlan.dat should be created or updated whenever you create, rename, change or delete a VLAN or when you modify the VTP settings (VTP domain name, VTP mode, VTP password). Any of these changes should result in updating the vlan.dat file. So for example, I suggest adding a few VLANs, verifying that they exist, and removing them afterwarsd. That should reestablish your vlan.dat file.

Regarding the DHCP, is it perhaps possible for you to post the entire configuration here? And also please include the show vlan or show vlan-switch output.

Best regards,


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