When a hostname is too long docker won't start

[davidsandilands]

Describe the bug
In environments like azure where the hostname can be absurdly long "pe-server-0-d6a9f5.vhcpsckl41fedgadugqovud0sa.cwx.internal.cloudapp.net" docker will fail to start using the default value for hostname of the FQDN as per betadots/hdm#123.

To Reproduce
Use an server with a hostname FQDN with I think 24 characters or more. I'm not sure of the exact limit

Expected behaviour
The most reasonable thing I could find to do this was just using the shortened hostname. So I would suggest a check to ensure the FQDN does not exceed limits and if it does either failing or substituting in shortened name (with warning ? )

HDM Server (please complete the following information):
All versions

Additional context
betadots/hdm#123

[ekohl]

We had a similar issue that caused us to revert back to short names elsewhere: voxpupuli/gha-puppet#26, which partially reverted voxpupuli/gha-puppet#22.

[tuxmea]

Is this related to Docker only? Does someone know if this might also be an issue when we use podman instead of docker?