Yes, that would be my recommendation: use the testing domain to your hearts content, when you're satisfied it does what you want then you can rename the doam to your live system and set-up and internal DNS records for that( (should you need them) and that should suffice.
Originally Posted by pjmelvin
Be aware that during the initial install you would have been asked if you wanted to change the domain name (you only get asked at this one point), if you did not do that it would have the FQDN of your server as the domain name rather than 'doman.com' which is what you want. If that's what has happened I'd suggest you remove Zimbra from the server with './install.sh -u' that will remove everything and you can reinstall and set the domain name correctly.
Before you do the reinstall and after you've set the hosts file and DNS records you can check them with the following (on the zimbra server):
That will give you everything you need to confirm if it's OK. If you don't understand anything or have more questions please post the output of those commands here - don't forget the c'code' formatting.
host `hostname` <-- use backticks not single wuotes
dig yourdomain.com mx
dig yourdomain.com any