# Discourse-setup using netcat with illegal option combination? **URL:** \ **Category:** Self-hosting\ **Created:** [August 26, 2023, 12:54pm UTC](https://meta.discourse.org/t/discourse-setup-using-netcat-with-illegal-option-combination/276762 "2023-08-26T12:54:10Z")\ **Posts on this page:** 1\ **Showing post:** 1
**Author:** ![steinhh](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/steinhh/32/242776_2.png) [@steinhh](https://meta.discourse.org/u/steinhh)\ **Post date:** [August 26, 2023, 12:54pm UTC](https://meta.discourse.org/t/discourse-setup-using-netcat-with-illegal-option-combination/276762/1 "2023-08-26T12:54:10Z")
Using the standard [discourse/docs/INSTALL-cloud.md at main · discourse/discourse · GitHub](https://github.com/discourse/discourse/blob/main/docs/INSTALL-cloud.md) installation procedure on Centos 7, but: The network connectivity on ports 80 & 443 is tested with nc thus: ```plaintext echo -e "HTTP/1.1 200 OK\n\n $VERIFY" | nc -w 4 -l -p $PORT >/dev/null 2>&1 & if curl --proto =http -s $HOST:$PORT --connect-timeout 3 | grep $VERIFY >/dev/null 2>&1; then : ``` But nc fails with ```plaintext nc: cannot use -p and -l ``` making the setup script report unavailability on those ports. man nc says: ```plaintext -l Listen for an incoming connection rather than initiating a connection to a remote host. Cannot be used together with any of the options -psxz. Additionally, any timeouts specified with the -w option are ignored. ``` It may be an nc version problem, I see [NC](https://www.commandlinux.com/man-page/man1/nc.1.html) does _not_ say that there’s any conflict with the two. My netcat can listen, but only using ```plaintext nc -w 4 -l ``` Can’t get netcat to tell me its version number 😕 --- _[View the full topic](https://meta.discourse.org/t/discourse-setup-using-netcat-with-illegal-option-combination/276762)._