OpenWRT DDNS: Difference between revisions

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Error loading shared library libbind9-9.18.7.so: No such file or directory (needed by /usr/bin/nsupdate)

</syntaxhighlight>Try reinstalling the bind-libs package: opkg update bind-libs (or remove it and reinstall it, etc.)

=== Script Error for NSUPDATE (and possibly other scripts too) ===

If a DDNS update is being sent to a "non-default" port, IE instead of port 53 (udp or tcp), say port 5353, how is that done?

...well, the OpenWRT LuCI interface doesn't give any sort of hint. But, if one looks inside the /usr/lib/ddns/dynamic_dns_lucihelper.sh Script, there's a line that says this: -d DNS-SERVER => dns_server=SERVER[:PORT]

OK, great. The dns_server / DNS-SERVER variable(s) equate to the DNS-Server Field in the LuCI GUI, so the format would be: W.X.Y.Z:WhatEverPort (where W.X.Y.Z can be an IP Address or Host Name) Right? Nope. It will give this error when the DDNS service is restarted: CRIT : sanitize on dns_server found characters outside allowed subset - TERMINATE

<nowiki>Hmmm, what could it be. Ah! "Behind the scenes", the OpenWRT DDNS update scripts are using the NSUPDATE command / binary from BIND / NAMED (look closely at what gets installed when the ddns-scripts-nsupdate package is installed and you'll notice that the bind-tools package is also installed, which includes the NSUPDATE command). So how does NSUPDATE format the IPAddress:Port thing? They use a space, instead of a colon ( : ). From NSUPDATE help: server address [port]</nowiki>

OK, great! So instead of W.X.Y.Z:WhatEverPort, it would be W.X.Y.Z WhatEverPort. Nope. Same error: CRIT : sanitize on dns_server found characters outside allowed subset - TERMINATE

Why is that?

So in conclusion, here's are the issues;

* The LuCI GUI gives no indication of what the Host / IP Address [Port] Syntax should be (maybe because nothing will work)

* The dynamic_dns_lucihelper.sh script has a clear indication of the syntax. But sadly it doesn't work (anymore?, maybe it did in the past or someone has it in mind for the future?).

* The Regular Express in the dynamic_dns_functions.sh script file does not facilitate or allow spaces or colons (it shouldn't allow colons, but should allow a space because the NSUPDATE command allows for spaces), so this makes it impossible to add / change the default DNS port number (which is NECESSARY sometimes!, see comment below)

* The "NSUPDATE Script" that is generated and "temporarily" (it only seems to keep the script there if there is an error, otherwise the IP address is stored there) stored in /tmp/run/ddns/WhateverName.DAT contains the NSUPDATE commands, one line of which is: server W.X.Y.Z [and can have the port number, but isn't put there by OpenWRT's DDNS script, but could be put there, but a space, not a colon is the correct syntax]. This means the "NSUPDATE Script" generated by OpenWRT's DDNS script never has the port number included (but it could)

*

And all of the above might be putting the cart before the horse, so here's the 'cart' (IE, the problem that being able to put in a different port number solves): Some internet providers like Comcast use some type of 'transparent' (in real world terms that would be evil and selfish) DNS proxy service that interferes with OpenWRT DDNS updates. This is a known 'issue' (Google it) was tested extensively to verify (a subject for another article coming soon).

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@@ Line 423: / Line 423: @@
 Error loading shared library libbind9-9.18.7.so: No such file or directory (needed by /usr/bin/nsupdate)
 </syntaxhighlight>Try reinstalling the bind-libs package: opkg update bind-libs (or remove it and reinstall it, etc.)
+=== Script Error for NSUPDATE (and possibly other scripts too) ===
+If a DDNS update is being sent to a "non-default" port, IE instead of port 53 (udp or tcp), say port 5353, how is that done?
+...well, the OpenWRT LuCI interface doesn't give any sort of hint.  But, if one looks inside the /usr/lib/ddns/dynamic_dns_lucihelper.sh Script, there's a line that says this: -d DNS-SERVER       => dns_server=SERVER[:PORT]
+OK, great.  The dns_server / DNS-SERVER variable(s) equate to the DNS-Server Field in the LuCI GUI, so the format would be: W.X.Y.Z:WhatEverPort (where W.X.Y.Z can be an IP Address or Host Name)  Right?  Nope.  It will give this error when the DDNS service is restarted: CRIT : sanitize on dns_server found characters outside allowed subset - TERMINATE
+<nowiki>Hmmm, what could it be.  Ah!  "Behind the scenes", the OpenWRT DDNS update scripts are using the NSUPDATE command / binary from BIND / NAMED (look closely at what gets installed when the ddns-scripts-nsupdate package is installed and you'll notice that the bind-tools package is also installed, which includes the NSUPDATE command).  So how does NSUPDATE format the IPAddress:Port thing?  They use a space, instead of a colon ( : ).  From NSUPDATE help: server address [port]</nowiki>
+OK, great!  So instead of W.X.Y.Z:WhatEverPort, it would be W.X.Y.Z WhatEverPort.  Nope.  Same error: CRIT : sanitize on dns_server found characters outside allowed subset - TERMINATE
+Why is that?
+So in conclusion, here's are the issues;
+* The LuCI GUI gives no indication of what the Host / IP Address [Port] Syntax should be (maybe because nothing will work)
+* The dynamic_dns_lucihelper.sh script has a clear indication of the syntax.  But sadly it doesn't work (anymore?, maybe it did in the past or someone has it in mind for the future?).
+* The Regular Express in the dynamic_dns_functions.sh script file does not facilitate or allow spaces or colons (it shouldn't allow colons, but should allow a space because the NSUPDATE command allows for spaces), so this makes it impossible to add / change the default DNS port number (which is NECESSARY sometimes!, see comment below)
+* The "NSUPDATE Script" that is generated and "temporarily" (it only seems to keep the script there if there is an error, otherwise the IP address is stored there) stored in /tmp/run/ddns/WhateverName.DAT contains the NSUPDATE commands, one line of which is: server W.X.Y.Z [and can have the port number, but isn't put there by OpenWRT's DDNS script, but could be put there, but a space, not a colon is the correct syntax].  This means the "NSUPDATE Script" generated by OpenWRT's DDNS script never has the port number included (but it could)
+*
+*
+And all of the above might be putting the cart before the horse, so here's the 'cart' (IE, the problem that being able to put in a different port number solves): Some internet providers like Comcast use some type of 'transparent' (in real world terms that would be evil and selfish) DNS proxy service that interferes with OpenWRT DDNS updates.  This is a known 'issue' (Google it) was tested extensively to verify (a subject for another article coming soon).
+<br />