Citrix Provisioning Services, Bluecat DHCP Appliance and PXE-E32: TFTP Open Timeout Error
January 9, 2014
At a recent XenDesktop and PVS project we ran into an issue where even though DHCP Options 66 and 67 were configured, we could not get rid of the PXE-E32: TFTP open timeout error. This short article describes the resolution.
This project was for XenDesktop 7.1 and PVS 7.1 using Bluecat DHCP/DNS appliances. There are a couple of search hits that mention this specific issue with Bluecat DHCP where DHCP Option 66 is never returned in the DHCP Offer packet. We made sure of the following:
- All PVS servers had the correct IP addresses, subnet mask and gateway
- The boot configuration file in both PVS sites was configured with the correct subnet mask
- The VLAN was configured with the right subnet mask
- DHCP was configured with the right subnet mask and gateway
- DHCP Options 66 and 67 were configured correctly
We did find some subnet misconfiguration issues and all subnet masks were corrected. We then reran the PVS Configuration Wizard and make sure the correct subnet mask was used for the boot configuration information. But we still received the PXE-E32: TFTP open timeout error.
We then installed Wireshark on the PVS server used for Option 66. After receiving the timeout, we stopped the Wireshark capture and analyzed the DHCP packets. What we noticed was that there was no Option 66 in the DHCP Offer packets. DHCP Option 67 was there but without Option 66 the target device had no IP Address to go to for Option 67. The customer placed a support call to Bluecat and found out that the Bluecat DHCP appliances do not support Option 66 or Option 67. Bluecat has their own proprietary options that act like Options 66 and 67. Once the proprietary options were set on the Bluecat DHCP appliance, the PXE-E32: TFTP open timeout error was gone, the target device received the proper information for the TFTP Server and boot file and the project was able to proceed.
Unfortunately the Bluecat support knowledgebase is behind a paid login so you will not find this information anywhere. I hope this short post will help others out there looking to resolve the missing DHCP Option 66 offer when a Bluecat DHCP appliance is used.
UPDATE 10-Jan-2014: The customer gave me permission to include the settings that need to be set on the Bluecat DHCP appliance. These are not DHCP Options, just fields on the Bluecat: