PXE boot fails with "PXE-E53: No boot filename received" only on a VM vlan

Products

• Deployment Solution

Issue/Introduction

Attempting to network boot endpoints on a different subnet/vlan from where the NBS/PXE server resides. Between the PXE server and endpoints that are network booting there is a Cisco ACI fabric equipment acting as a DHCP relay.

The ACI fabric network is dropping offers that do not include Option 82 - it appears our NBS server does not offer option 82 so the offer is silently dropped by the fabric.

Environment

ITMS 8.6 RU2

Cause

Cisco ACI fabric with IP helpers is dropping DHCP offers (from PXE/NBS) because they do not include Option 82.

Wireshark capture shows no Option-82 offered from PXE/NBS and this appears to be standard for most PXE servers.

Resolution

A Feature Request has been entered to have the NBS/PXE respond with option 82 in the offer.

Workarounds:

• Create a bootable ISO of the preboot environment and boot to that on the VM’s
• Place a PXE server on a supported OS within the VM environment the clients are able to PXE boot to without issue
• Create and deploy Automation Folders to the endpoints

Additional Information

KB Document:
https://social.technet.microsoft.com/Forums/windowsserver/en-US/25741e50-bcdd-47aa-ba99-4199d6e5a7fa/clients-fail-to-pxe-boot-in-cisco-aci-environment?forum=ConfigMgrCBOSD

DHCP Relay Section:
 https://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/1-x/aci-fundamentals/b_ACI-Fundamentals/b_ACI-Fundamentals_chapter_010100.html#concept_1D4F7C5492704AE0ACD6B8034A53C63A

Customer using Cisco, not Juniper but same issue:
https://www.juniper.net/documentation/en_US/junos/topics/reference/general/managing-dhcp-pxe-bootp-servers-do-not-support-option-82.html