CentOS Minimal Installation - Ports blocked?
I am trying to connect to a new CentOS 7 server to do some performance testing. It is a minimal install and at this point the only things installed / configured are to test RAID performance, Java 1.7 and Wowza Media Server which has a web service that runs on port 8088. I am able to SSH / Sftp into the server all I want, but can't connect to the port 8088 from my windows computer.
The 2 computers are on the same network, and the switch has that port open as I can tie into the Ubuntu server sitting next to it on port 8088. Using the lynx command line browser on the CentOS server, I can open the site using localhost, or it's IP address as well. There are no rules configured by me in iptables or /etc/hosts.deny. I have looked at all the tips I could think of to see what is open using netstat, or nmap and don't see what is going on. What am I missing here?
You can see port 8088 open here:
[root@localhost sysconfig]# netstat -tanp | grep LISTEN
tcp 2 0 127.0.0.1:25 0.0.0.0:* LISTEN 2490/master
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1694/sshd
tcp 0 0 0.0.0.0:8088 0.0.0.0:* LISTEN 1781/java
tcp6 0 0 ::1:25 :::* LISTEN 2490/master
tcp6 0 0 :::22 :::* LISTEN 1694/sshd
[root@localhost sysconfig]# nmap -sT -O 192.168.1.75
Starting Nmap 6.40 ( http://nmap.org ) at 2015-01-06 11:05 MST
Nmap scan report for 192.168.1.75
Host is up (0.0024s latency).
Not shown: 998 closed ports
PORT STATE SERVICE
22/tcp open ssh
8088/tcp open radan-http
Device type: general purpose
Running: Linux 3.X
OS CPE: cpe:/o:linux:linux_kernel:3
OS details: Linux 3.7 - 3.9
Network Distance: 0 hops
Turns out it was a firewall configuration from the default installation. Live and learn. This is what I ended up finding: https://www.centos.org/forums/viewtopic.php?f=47&t=47129
firewall-cmd --zone=public --permanent --add-port=8088/tcp
Note that you have to restart the service before you can see the changes.
If you want to test it without restarting the service, you can remove the --permanent flag; however, the rule will expire as soon as the service restarts.