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On 17-Nov-17 18:04, Mark Andrews wrote:<br>
<blockquote type="cite"
cite="mid:ACED0C24-C949-4FAB-BD94-B2F03A1E4780@isc.org">
<pre wrap="">DYN used to just require a TSIG signed update request set to a server specified in
a SRV record.</pre>
</blockquote>
Depends on which service. The one I referred to is the one that was
popular (free) for people who wanted to reach a machine on a dynamic
IP address. Because it was popular, it was implemented in a number
of routers, including Linksys (low end) and Cisco (IOS). I believe
they discontinued the free version, but the protocol lives on.<br>
<br>
It's worse than DNS UPDATE in an number of respects - but is trivial
to implement in a router or script as the core is just an HTTP GET.<br>
<blockquote type="cite"
cite="mid:ACED0C24-C949-4FAB-BD94-B2F03A1E4780@isc.org">
<pre wrap="">
We have a perfectly fine protocol for updating the DNS but DNS hosting companies
want to reinvent the wheel.
</pre>
</blockquote>
Agree. I wish that the DNS UPDATE protocol was the only one in the
wild. Unfortunately, (non-jail broken) routers don't provide that
option, but do provide the http ("dyn") version. So if you want to
use a service that requires it - or want to bridge a router that
supports it to DNS UPDATE, some invention is required. I outlined
an approach that works for me.<br>
<br>
For reference, cisco's IOS (now) supports both methods - to some
extent.<br>
<br>
See <a moz-do-not-send="true"
href="https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_dns/configuration/15-sy/dns-15-sy-book/Dynamic-DNS-Support.html#GUID-DCA9088D-EB90-46DE-9E33-306C30BB79CE">https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_dns/configuration/15-sy/dns-15-sy-book/Dynamic-DNS-Support.html#GUID-DCA9088D-EB90-46DE-9E33-306C30BB79CE</a><br>
<br>
And from that page, here's the reference to dyndns (you can change
the URI for other http services; it lists 6 others)<br>
<blockquote>add
<a class="moz-txt-link-freetext" href="http://test:test@members.dyndns.org/nic/update?system=dyndns&hostname=">http://test:test@members.dyndns.org/nic/update?system=dyndns&hostname=</a><h>&myip=<a><br>
</blockquote>
I use https, of course.<br>
<br>
Naturally, IOS doesn't support TSIG - so DNS UPDATE from it has to
be authorized by IP address. :-(<br>
<br>
2136/7 have been around since 1997, so there's really no excuse for
DNS providers not tosupport them.<br>
<br>
But we live in a world of excuses :-(<br>
<br>
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