@Simran Kaur All ports 1024 and below are considered reserved as privileged ports and can be only used/bound to by process run by the root user. NiFi can use these ports if it is running as the root user. The alternative is to setup your ListenHTTP processor to run on a non privileged port and then set up port forwarding in your iptables to redirect incoming requests to a privileged port to that non privileged port you are using in NiFi: iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-ports 8081 Thanks, ... View more