Edge Router DHCP Option 66 (the easy way)
Set up the subnet with an option appended i.e. set service dhcp-server shared-network-name [Name_of_Scope] subnet [IP_Subnet] tftp-server-name '[Path_To_Resource]'
E.g. for 192.168.2.0/24 subnet it might look like this:
set service dhcp-server shared-network-name PROVISIONING subnet 192.168.2.0/24 tftp-server-name 'tftp://192.168.2.100/57977/'