PXE-E55: Proxy DHCP service did not reply to request on port 4011

  • 3808022
  • 26-Jul-2006
  • 30-Apr-2012


Novell ZENworks for Desktops 4.0.1 - ZfD4.0.1
Novell ZENworks Desktop Management 6.5 - ZDM6.5
Novell ZENworks Desktop Management 7 - ZDM7
Novell ZENworks Desktop Management 7 - ZDM7 Imaging
Novell ZENworks Desktop Management 7 - ZDM7 PreBoot Services (PXE)


Error: PXE-E55: ProxyDHCP service did not reply to request on port 4011.
Unable to PXE boot workstation.
DHCP Tag Option 60 is enabled.
DHCP Tag Option 43 is enabled.


If DHCP and PDHCP are running on separate servers, check to make sure that the Tag 60 is NOT set in the global options for DHCP.

In a Novell Cluster Services environment, try these steps to resolve the symptom of the PDHCP server not responding:

1- Make sure that the PDHCP.NLM, PXESTART, etc. are not loading in the autoexec.ncf. They should load only from the NCS load scripts if they are intended to be a Cluster resource.

2- The PDHCP.INI should not be edited with IP addresses to bind the services to. The NLM does auto-discovery of the real and the resource IPs, and will work correctly if it is allowed to do so.

3- Typically, the TFTP directory should be on the shared, or virtual, SYS:\SYSTEM folder in the Cluster.

4- Note that even if the services are in the same Cluster, they are still on different servers, so the Option 60 rule still applies. Set the Option 60 Tag in DHCP if they are on the same node, but do not set it if they are on different nodes in the cluster. The Option 60 change is not dynamic, so do not set the PDHCP and DHCP services to fail over "on top" of each other.
NOTE: DHCP Tag Option 43 can cause the workstation to no respond to DHCP offers from the DHCP server and PDHCP server.

Additional Information

Formaly known as KB 10085945.

The best way to troubleshoot this error message is to perform a packet trace while the workstation is attempting to boot. What you should see in the trace is the workstation send a DHCP Discovery packet to the broadcast address. Then, there should be two DHCP Offer packets returned immediately to the workstation. One of them should be from DHCP with all the IP addressing information, Options 53, 54, 51, 1, 6, etc. The second DHCP Offer should be from the PDHCP server, and should include the Option 60, as well as some others, like Option 93, 94 and 97.

If the workstation sends 3 or 4 DHCP Discovery messages, and does not receive the PDHCP response it needs, then it will fail the PXE process and go on to the next boot device, typically the C: drive.