Why RHEV guests fails when booting via PXE + dnsmasq?

  • Adding the following line to dnsmasq.conf resolves the issue
dhcp-no-override

Root Cause

  • A potential issue may exist when trying to find the boot filename when using gPXE + dnsmasq.
--dhcp-no-override
              (IPv4  only)  Disable re-use of the DHCP servername and filename
              fields as extra option space. If it can, dnsmasq moves the  boot
              server  and  filename  information (from dhcp-boot) out of their
              dedicated fields into DHCP options. This make extra space avail‐
              able in the DHCP packet for options but can, rarely, confuse old
              or broken clients. This flag forces "simple and safe"  behaviour
              to avoid problems in such a case.

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