I've just installed Jenkins with its default configs on a Centos 7 physical box.
Port 8080 is open on the firewall:
sudo iptables -L -n [...] ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:8080 [...]
It also looks like Jenkins is actually listening on all interfaces:
sudo netstat -an | grep "LISTEN " [...] tcp6 0 0 :::8080 :::* LISTEN [...]
curl localhost:8080 locally (from the Centos box) without a problem, but from anywhere else in the network I get a
Am I missing something?