If they try to login using servername “auzern”, then this name should be resolvable (either in DNS or in their hosts file). Give us more info. Are they on your local network? Then they can try logging in using IP address of your machine. If they are outside your network you may have to open some ports on a router and forward them to your machine (5222 port at least). Also check your firewall whether it is not blocking incoming traffic to the port 5222.
You dont have to open 9090, 9091 as these ports are only for Admin Console.
I suppose your server name is not in DNS system, so outside users simply cant see it by its name. They should try putting external IP address of your router in the Server field.
I dont have any experience with Internet web server DNS system. At office we have put a record in Windows Server DNS service which is pointing all requests to “openfire_server” to the corresponding local IP. If you can manage DNS records in your web site/hosting management, then you can try doing this. Though i think this can be not possible to set a record for just “server”. It has to have the domain part i think, like .com. Then you can have problems if your server’s name won’t match this DNS record. I suggest to wait till someone with more experience replie here or search the forums for other threads about DNS SRV records. Also, DNS servers won’t update immediately. It usually takes some time, day or two.
Now what I thought was, I will bring all the users onto a virual private network and then open up a private server with just a name and then telling them to join in. Will this be possible?
Don’t know how will it work with the VPN. I think they still will have to use IP address instead of the name, but in this case maybe internal IP of your computer.