This entry starts the instsrv service when required. This service should be disabled. The instsrv service is part of the Network Installation Tools, used for servicing servers running AIX 3.2. This is no longer applicable for modern AIX installations.
Solution
In /etc/inetd.conf comment out the instsrv entry: chsubserver -r inetd -C /etc/inetd.conf -d -v 'instsrv' -p 'tcp' refresh -s inetd