iptables -L
ah, but:
I’m not entirely sure where Centos 7 is in relation to Fedora as I’m still stuck in 32 bit land and haven’t used it, but in the latest Fedora you have firewalld instead of iptables. It used to be standard practice just to do:
service iptables stop
to get that one out of the way when testing any network stuff, but now the equivalent runes are:
systemctl stop firewalld
systemctl disable firewalld
…you then have to reboot, as the firewall doesn’t reliably get out of the way until you’ve done that.
(not that I always do any more as it’s so easy to punch holes in firewalld, I much, much prefer it)