Open firewall port on CentOS 7

Question

I am using CentOS 7 and I have to ensure that ports 2888 and 3888 are open. I read this article but this did not work because on CentOS 7 OS there is no `iptables save` command. Someone told me that the above URL is not valid for CentOS 7. and I should follow this. But this article is not clear to me on exactly what command I need to execute. I also found ``` firewall-cmd --zone=public --add-port=2888/tcp ``` but this does not survive reboots. So how can I open the ports and make it survive reboots?

Accepted Answer

Use this command to find your active zone(s):

```
firewall-cmd --get-active-zones
```

It will say either public, dmz, or something else. You should only apply to the zones required.

In the case of public try:

```
firewall-cmd --zone=public --add-port=2888/tcp --permanent
```

Then remember to reload the firewall for changes to take effect.

```
firewall-cmd --reload
```

Otherwise, substitute public for your zone, for example, if your zone is dmz:

```
firewall-cmd --zone=dmz --add-port=2888/tcp --permanent
```

Open firewall port on CentOS 7

Solution

Problem