Dynamic DNS settings for AVM FritzBox router

[dirtyharry_28]

I am using OpenDNS since yesterday and have set it up in my router (AVM Fritz!Box 7330) using the infos for the dynamic IP update which I gathered searching the internet and tried the following configurations:

Config 1:
Update-URL: updates.dnsomatic.com/nic/update?myip=<ipaddr>
Domainname: dnsomatic
Username: [my DNS-O-Matic username]
Password: [my DNS-O-Matic password]

with this config the IP update works (can be seen on DNS-O-Matic and OpenDNS) but my router shows this in the log:
"Dynamic DNS-Fehler: Der angegebene Domainname kann trotz erfolgreicher Aktualisierung nicht aufgelöst werden"
which means "Although update was successful the domain name could not be resolved". Sure it has no TLD.

The "domainname" entry in the router is the customer URL from the dynamic DNS provider which makes the router available from external, like "myusername.dyndns.org".

I did not find any information on the OpenDNS and DNS-O-Matic website what this "domainname" could be. I also tried dnsomatic.com but without success, same with "localhost" - then the error gets even worse:
"Dynamic DNS-Fehler: Die Dynamic DNS-Aktualisierung war erfolgreich, anschließend trat jedoch ein Fehler bei der DNS-Auflösung auf."

Means: Update was successful but an error in DNS resolving occured afterwards" although I can normally access websites.

Currently trying to update directly via OpenDNS instead of DNS-O-Matic using this config.

Config 2:
https://updates.opendns.com/nic/update?hostname=home
opendns
Username: [my OpenDNS username]
Password: [my OpenDNS password]

(where "home" is the name for the registered network associated with my account)

With every config I get this error described below config 1) every 30 minutes - which seems to be the interval for the router to send an IP address update to a dynamic DNS service.

My question now is:
what should I use as proper "domainname" in the dynamic DNS settings to use with OpenDNS dynamic IP updates?

Maybe "OpenDNSusername.opennds.com" or "OpenDNSusername_networkname.opennds.com"?

Thanks a lot!

Timo

[rotblitz]

To (almost) prevent this warning message to appear, you'll have to use a real dynamic DNS hostname which is updated as well and points to your IP address then.  The reason is: your router checks for the success of the update afterwards, and any made-up hostname like "dnsomatic" or "dnsomatic.com" or "OpenDNSusername.opennds.com" or "OpenDNSusername_networkname.opennds.com" causes the test to fail and to raise this warning message if the hostname does not exist or points to the wrong IP address.

See at DNS-O-Matic what services are supported, and select a free service from there to subscribe to it to get a hostname you can enter in your router, and keep this updated through DNS-O-Matic as well, same as your OpenDNS service.

Btw, the update URL of Config 1 is most likely the right one.  I would not know that AVM devices support HTTPS at all.  But I may be wrong.

[alexahar]

While we are working on this case in your ticket, I will hold this space as a placeholder for DDNS information regarding the AVM Fritz!Box 7330 router. 

It may be the case that this router only supports DDNS updates for a dynamic IP hostname to allow remote connections into the router, and may not support OpenDNS IP updates out of the box. 

[dirtyharry_28]

Hello Rotblitz,

thanks for your post. That´s what I found out in the meantime but as some say it works with whatever you add as domain name (dnsomatic, localhost etc) I was confused.

In the meantime I have registered a DDNS account at one of the services supported by DNS-O-Matic and added this server name to my Fritz!Box as domain name. For 2 days I still got this "Dynamic DNS-Fehler: Die Dynamic DNS-Aktualisierung war erfolgreich, anschließend trat jedoch ein Fehler bei der DNS-Auflösung auf." error but only 2 times and only when the box reconnects after the forced 24h ISP disconnect, before it was every ~30mins. Today I did not get any error after reconnect, no idea why.

What service do you use with the "domain name" field? Did you enable remote access via HTTPS for the box?

[rotblitz]

"For 2 days I still got this "Dynamic DNS-Fehler: Die Dynamic DNS-Aktualisierung war erfolgreich, anschließend trat jedoch ein Fehler bei der DNS-Auflösung auf.""

But the update was successful, as the message says.  And this is the important point.  You may still occasionally get this error message. You can safely ignore it, or ask AVM to increase the time after they check whether or not the update was successful.  They apparently don't wait long enough to check.  It should be at least one minute, better three, not just a few seconds.  DDNS updates take a short while, depending on many factors like the TTL and local and remote caching.

Also, there is no rule (and most likely no need) to check afterwards for a DNS resolution (DNS-Auflösung) against the configued hostname.  Rather to the contrary: some official APIs forbid this checking against hostnames.  AVM are not compliant with these rules.

"before it was every ~30mins."

This could have several reasons.  Your ISP may have changed your IP address so often, or your AVM device has a severe bug raising unnecessary (abusive) DDNS updates too often under certain circumstances where using an non-existent hostname (as you did) would be a good reason for.

All that said, you can't do anything more except to provide AVM with these options: either getting rid of this unnecessary check or make it optional (preferred), or increasing the wait time before they check.

[dirtyharry_28]

It seems random when I get these 2 errors, some days I get them, some days I don´t. But I can live with that.

I don´t think AVM will increase the timeout only for me :) Found several tutorials how to add a new DDNS service via editing an exported settings file where you can manually set values like time out / TTL but I don´t want to brick my box by importing an edited settings file which is not 100% correct .

IP address is definitely only changed once (if DSL sync does not lost) and always between 4 and 5 AM (as set in the Fritz!Box). My assumption is that (before I added the "dummy" DDNS service as domain name) it frequently tries to resolve and if it does not work it tries again and again. But now with adding a dummy DDNS service, for which I created an account but not use it, the box will stop showing the error as soon as the domain name could be resolved before the defined time out of the box.

So far, I am fine with it. Hope this may help other Fritz!Box users.

@Support: I once opened a support ticket asking if you need a short description with screenshots for an AVM Fritz!Box to add to your router tutorials as AVM models are completely missing there and this type of router is very popular in Germany as they are sold by a big German ISP together with their service.

[alexahar]

I've reached out to you on a support ticket so we can work together to create some FritzBox documentation on our router configuration guide. We'd love to have screenshots and descriptions!

[Anonymous]

Is there a documentation for FritzBoxes yet? I could not find it. I would love to have one and i would also like to support or test a documentation.

[rotblitz]

The documentation is your AVM user manual.

[dirtyharry_28]

@Alexander & Jantietje: I could share my experience and settings with an AVM Fritz!Box using OpenDNS if you like

[rotblitz]

We all know:

First you must register your OpenDNS service at https://www.dnsomatic.com/ 
And you register a hostname with any other (free) DDNS provider supported by DNS-O-Matic which you register at DNS-O-Matic too.

Then you configure your FritzBox.  The same is valid for most other AVM supplied routers like Speedports.

Service: user defined (or DNS-O-Matic if supported)
Update URL: updates.dnsomatic.com/nic/update?myip=<ipaddr> 
Domainname: the hostname registered with this other DDNS provider 
Username: Your e-mail address registered with OpenDNS/DNS-O-Matic 
Password: your OpenDNS/DNS-O-Matic password 

That's all!

[Anonymous]

Thank for your support, my FritzBox is doing fine with opendns. I just want to ret rid of the error messages and looking forward to "some FritzBox documentation on our router configuration guide" with "screenshots and descriptions".

[rotblitz]

Isn't that too trivial?

[marcben]

I'm using Fritz!Box 7490 and it gives me the same message.

Anyway, it works correctly and all of the 6 services that are configured on the DNS-O-Matic service are correctly updated.

I think it should just be regarded as a warning, rather than a real error.

This is confirmed by the following help text you obtain clicking on the error message:

Dynamic DNS error: The dynamic DNS update was successful, but an error occurred during the subsequent DNS resolution.

This is an event message from the "Internet Connection" area.

The update request was confirmed by the DynDNS provider, but has not been implemented yet. After a few minutes your IP address will be converted automatically.

If you would like to check it, open your domain in a web browser.

If the connection cannot be established even after a long wait, contact your DynDNS provider.

[rotblitz]

And what is your question?

This error message is the same in English as reported in German by the original poster dirtyharry_28, and this has been answered by me, so nothing should be open to be answered.