Hello Matt,
The option 43 is based on your detailed configuration. and the option 43 format example is as below
80 07 00 00 01 C0 A8 01 01 //HEX
80: fixed value, no need to change;
07: length field, followed by the byte length of the data;
00 00: fixed value, no need to change;
01: indicates the number of subsequent IP addresses, here is one IP address;
C0 A8 01 01: IP address. //The IP address translated into decimal is 192.168.1.1 (C*16=192, A*16+8=168, 1*1=1, 1*1=1)