Try to type in the IP address manually to make sure you write it correctly.
no hostname
hostname.
With the following command: No hostname
ping hostname or nslookup hostname For more details: http://www.zilckh.com/how-to-find-ip-address-from-hostname-in-a-windows-system-using-command-line/
The hostname (the name of the computer) can be found in most Linux distributions by issuing the hostname command without arguments. Alternatively, you can view the contents of /etc/hosts. The hostname will be listed next to the IP address 127.0.1.1.
A hostname is the name a computer uses to identify itself to other computers on a network.
A hostname in an email address appears after the @ symbol, like user@hostname.com. The hostname is always the company or group that handles that email address.
DNS Server (Domain Name System) resolves Hostnames to IP Addresses in Internet.HOSTS file in Windows computers is responsible for resolution of hostnames to ip addresses.
pinging the hostname will resolve the ip for you Click START - RUN type CMD then Enter type Ping (Computername) then Enter
Hostname is more of a UNIX thing than a Mac thing ;-) It can be changed in the Sharing section of System Preferences where it is known as Computer Name.
DNS issue