- enable telnet
http://192.168.0.1/setup.cgi?todo=debug
- telnet to the dgnd3700v2
- Mount root partition rw to allow changes
mount mtd:rootfs / -o remount,rw
- cd /www
- Copy the original dynamicdns html file if you need to revert changes
cp DNS_ddns.htm DNS_ddns.orig
- Edit the dynamicdns html file with vi editor
vi DNS_ddns.htm
- find the line with <select name="sysDNSProviderlist" size="1"><option value="www.DynDNS.org">www.DynDNS.org </option></select>
- each <option> will be a dns provider option in the dropdown menu.
change the existing <option> or add new between the two select
for example <option value="dynupdate.noip.com">dynupdate.noip.com </option>
- save the edited file, as you know with vi editor command is :wq
- reboot to have root partition ro again and telnet disabled.