KNOCKDNS

KNOCKDNS FAQ

A dynamic DNS service operated by tcp port knocking

Well nobody has asked any questions yet, but if they did maybe they would go something like this...

• Whats your email address?
  knockdns@ ... then the domain name of this site.
• What kind of DNS records can I get?
  You will get an A record if you connect from an ipv4 address, or an AAAA record if you connect from an ipv6 address. You can connect via ipv4 and ipv6 and get both for a hostname.
• What subdomains are there?
  Right now only two subdomains are on offer dyn.koan.net and knockdns.com, but more may be added.
• How do I specify ipv6 or ipv4?
  The experimental knockd code at https://github.com/svalat/knock includes a knock client that can specify ipv4 ort ipv6. Also the "nc" (netcat) command available on Linux has a -4 or -6 option that can be used to replace the knock command if it is not available, similar to how telnet can be used.
• The knock command doesn't seem to work?
  Try using the --delay 40 parameter to add a 40ms delay between knocks.
• How do I use this with OpenWRT without installing the knock command?
  Luckily a tcp port knock doesn't need the "knock" command available, it can be done using a sequence of telnet attempts. In OpenWRT create a script called knock.sh or similar in the location /etc/hotplug.d/iface/ containing:

  
  #!/bin/sh
  telnet knockdns.com num1 2> /dev/null
  telnet knockdns.com num2 2> /dev/null
  telnet knockdns.com num3 2> /dev/null
  telnet knockdns.com num4 2> /dev/null
  

  and make it executable with chmod +x /etc/hotplug.d/iface/knock.sh and the knock update will be executed when OpenWRT connects. Replace num[1-4] with the sequence of numbers you were emailed when you signed up for a KNOCKDNS hostname.
• How permament or free will this site be?
  Thats hard to say. Right now its just a small project to test the waters after an earlier rough version filled a need better than the other big name services out there. Donations will help keep us interested in keeping this project afloat. The current implementation doesn't scale well with large numbers of hostnames, but domains registered with cryptocurrency donations will help keep the enthusiasm levels up for reworking the site as it gets close to the limit.
• I have an excess of useless cryptocurrency and want to donate it to KNOCKDNS, where should I send it?
  Here are the donation addresses for three common cryptocurrencies:

  bitcoin:3CKL2rezLUSaFqjekRUhoErUmLa7ez4xKi
  litecoin:MJniE7y7eTSUQt4u199gpvC1zbTqvpuWyT
  dogecoin:D8j8Jk9JbCABU21G3r2UCdqnguixo2Qv8c

  KNOCKDNS