If you have the A record in DNS but not the reverse ipa-replica-prepare fails to install even if you provide the --ip-address option.

I see a few issues in the way the address is checked.

First we should give verify_fqdn specific exception and not parse the text of a generic error message. That is a bit gross, and is what is making stuff fail here because we get back "Unable to resolve the reverse ip address, check [...]" while we expect "Unable to resolve host name". But in general relying on parsing error strings seems wrong, this code will break if in future we want to internationalize error messages.

Second when an --ip-address is passed and we do have DNS installed we should probably simply override what's in the DNS (perhaps in interactive mode warn and ask for confimration that we will change an actual existing record if the A record currently in DNs does not match).