This error indicates that the DNS name you are trying to resolve does not exist.
Things to try:
Check that the hostname portion of the
URL you are using is correct.
Check that iPXE is using the correct
DNS server. You can view the
DNS server used by iPXE using the command
show dns
:
iPXE> show dns
net0.dhcp/dns:ipv4 = 10.0.0.6