DNS-SRV is an extension to regular DNS records that gives domain operators additional configuration options. In our case, we are able to offer you automatic backup-routing.


Your hardware must first support the DNS-SRV feature. It can be assumed that this is the case with most current telephone systems.

Unfortunately, in view of the large number of devices, we cannot make a general statement on this. If in doubt, consult the documentation of your device or the manufacturer.

Users whose devices register with the Cloud Telefonanlage do not have to adjust anything, because the corresponding registrar supports DNS-SRV out of the box.


  1. Please call up the settings for VoIP registration in your telephone system or device.
  2. Find the Registrar field and change the entry as follows:
    Instead of, please use
  3. Restart the device or renew its registration manually.
  4. If problems occur with the connection, please check if your firewall allows traffic for


At present, enctypted telephony and DNS-SRV cannot be used simultaneously, because the registrars for encrypted calling do not support DNS-SRV, yet.

We are working on providing this function successively with all registrars.