I am trying to set dhcp option 60 and 61 for sky fiber dhcp client mer settings which are ontop of infinity which means your 2850 can be used for sky fiber
So I can use the vdsl port instead of the openreach modem plugged into the wan 2 port

srv dhcp custom_option-f
srv dhcp custom_option -t 0

srv dhcp custom_option-o 60-l firmwareversion|2ndHardwareSerial|skysg2|1stHardwa reSerial

srv dhcp custom_option-p 61-m PPPUsername|PPPPassword


or

send dhcp-client-identifier "pppoa-username|pppoa-password" but dont thats valid on draytek os

ian