dhcp_response probe unable to discover dhcp server
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dhcp_response probe unable to discover dhcp server


Article ID: 95531


Updated On:


DX Unified Infrastructure Management (Nimsoft / UIM)


Cannot configure monitoring of any DHCP Servers because none appear in the drop down list to create a monitoring profile for.

After deploying dhcp_response probe it is unable to discover any dhcp servers.

When I open the probe GUI I have observed following:

Under Profiles tab when I hit New to create a new profile there is nothing inside DHCP Server drop down menu.


Any supported UIM Server version
Any dhcp_response probe version through 1.68 (the current GA at the time of the publication of this document)


A review of the dhcp_response.log file captured after setting the probe's loglevel to 5 show that the probe is successfully sending the DHCPDISCOVER (BOOTREQUEST) broadcast messages. This is the request which is used to discover DCHP servers. If the logs show that the probe is not receiving a response from any DCHP servers in the network, then the probe cannot build a list of DHCP servers to create profiles from.

We expect to see a DHCPOFFER (BOOTREPLY) response in the log. This reply provides the probe with the information that can be decoded in order to display the DHCP server details in the probe's Configure GUI.

The lack of the DHCPOFFER (BOOTREPLY) response in the logs indicates that there may be a problem with the DHCP server itself not honoring the request from this system or failing to send the required response.

It is necessary to engage your DHCP admin team in order to determine why the DHCP servers are not replying to DHCP DHCPDISCOVER requests being sent by the dhcp_response probe on the robot it is deployed on.

Additional Information

The dhcp_response probe broadcasts DHCP DHCPDISCOVER requests and waits for DHCPOFFER (BOOTREPLY) responses to be returned by the DHCP Servers in the network to build a list of discovered DHCP Servers that you can created monitoring profiles.  If the request is not received by any DHCP Servers or the response is not sent or blocked the probe will not be able to discover any DHCP Servers.

Some network configurations that can cause this issue:
- Missing the configuration of a DHCP handler in the VLAN where the dhcp_repsonse probe is running
- MAC address used in the DHCP DHCPDISCOVER requests broadcast by the probe are not valid on any DHCP Server