Renew DHCP lease from CLI to a client connected to another Cisco device

[bulmers85]

I am trying to force a renewal of a DHCP lease provided by router A to client A, who is connected to the network via switch A.

From the router I can run the command 'renew dhcp lease', but I'm not sure what sub-command to use if my client isn't connected directly to the router. If it was directly connected to the router I would use 'renew dhcp lease fastethernet interface#' but none of the other options seem to fit my scenario.

Is it possible to renew a lease from the CLI to a client connected to a CDP neighbor?

[johnd2310]

Hi,

Can you not renew the DHCP lease from the client?

Thanks

John

[bulmers85]

I can, but there's a bigger issue at hand and this was one of my troubleshooting steps.

I have a department with Windows 7 clients. A few of them over the course of the last week have been unable to renew their DHCP lease automatically, and the only way I can get them back online is to assign them static addresses. There are plenty of available addresses in the pool, and other clients on the network are renewing their leases without any apparent issues, however I think the working clients are renewing their leases and being assigned the same IP.

In my testing, I discovered that when client A makes a DHCP request to this server, client A only receives a renewal if it is being assigned the same IP address. 

For example, client A has been assigned 192.168.2.15 by DHCP. I can recreate the issue experienced by the problematic clients by excluding 192.168.2.15 from the DHCP pool (to force it to get a different address). When I run ipconfig /release and /renew on client A, the /renew command times out and the client never gets assigned a new IP. When I remove 192.168.2.15 from the DHCP excluded list, the /renew completes and the DHCP server assigns client A 192.168.2.15.

If you have any thoughts on the larger issue, please, feel free to chime in.

[bulmers85]

Edit: duplicate