Android App: Unable to resolve host

Hi all,

currently I’m evaluating bitwarden.
I’m having quite some trouble using the android app because it can’t resolve the hostname of my self-hosted installation. The used version is the latest one from the official playstore.
The exact error message is:
Exception message: Unable to resolve host "mybitwarden.intranet.mydomain.com": No address associated with hostname.
The interesting thing is that I can copy the address on the same device and access the web UI in the browser.

Some information about my network:

  1. The issue happens on three different “devices” (2x android 11, 1x bluestacks 5)
  2. The server is hosted on docker and accessed via reverse proxy (using a self signed certificate for TLS that is imported to the android device)
  3. The DNS entry (mybitwarden.intranet.mydomain.com) is only available internally, i.e. although it’s an official domain, the intranet zone is only available on my network.
  4. The DNS entry is a CNAME pointing to a A-record of the docker host.
  5. The DNS name is only available for IPv4 my network also has partially IPv6.

Similar setups work for quite some other applications, so I wonder what is different to the bitwarden app that it can’t resolve the hostname. Has anybody seen this kind of behavior already?

Thanks,

Robert