You need to add an entry to the hosts file on your machine. The DSN needs to resolve to an IP and can't do so unless you tell it what IP to resolve to.
if you are on windows the file is here. C:\Windows\System32\drivers\etc\
on mac...no idea.
On a general note, the entry for the IP host name should be set up in the DNS such that a so-called "Reverse DNS lookup" works. With a "reverse DNS lookup" the Informatica software first asks the DNS for the IP address to a given host name and then it asks the DNS for the host name associated with the IP address; if they don't match, the domain will not start. And this check is very sensitive: for example, the host name abc123 does not match the name abc123.nowhere.com.
The sense of this double-check is to avoid IP spoofing attacks.
Could you please try the following commands in a CMD window / at the shell prompt of the server?
First: nslookup idqhostname
(this will return an IP address)
Second: nslookup ipaddress (with the IP address returned by the first nslookup)
If the host names do not match, then you should ask your network administrator(s) to correct the DNS entry for the IDQ host name.
In addition to what Nico suggested, please check if hostname for Informatica node (in $INFA_HOME/isp/config/nodemeta.xml) is defined with an IP address