I like to change our PXE configuration to use DHCP Option instead of IP-Helper configuration on a router. I delete the IP-Helper Entry on the router I set the DHCP Option 66 (IP Address of the ZCM Image-Server) and Option 67 (Bootfile: nvlnbp.sys).
If I boot the Client the follow error occures:

"PXE-E32_ TFTP open timeout".

We use a Infoblox Appliance for DHCP and ZCM 11.2.4 on w2k8 r2. All TFTP-Services are running and if I use the IP-Helper configuration all works fine!

The Preboot configuration-Files are not changed from the default.