Linux operating system How to configure the default firewall for an ECS instance -

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Overview

The default Firewall for CentOS 7 is Firewall, which replaces iptables. Firewall supports graphical interface management and command line management. This article describes how to configure the Firewall by using command lines.

Description

Start Firewall

After entering the system, the Firewall is installed on CentOS 7 by default but is not started. Therefore, you need to start the Firewall first and set it to start automatically at startup.

Log on to the ECS instance and run the following command to start the Firewall.
```
systemctl start firewalld
```
Run the following command to set automatic start upon startup.
```
systemctl enable firewalld.service
```

Common Commands

Run the following command to check whether the firewall status is running.
```
firewall-cmd --state
```
Run the following command to reload the configuration. For example, you need to run this command after adding a rule.
```
firewall-cmd --reload
```
Run the following command to list the supported zones.
```
firewall-cmd --get-zones
```
Run the following command to list the supported services.
```
firewall-cmd --get-services
```
Run the following command to check whether the FTP service is supported. If yes is returned, the FTP service is supported. If no is returned, the FTP service is not supported.
```
firewall-cmd --query-service ftp
```
Run the following command to start FTP:
```
Firewall-cmd -- add-service = ftp
```

Run the following command to start FTP:

firewall-cmd --add-service=ftp --permanent

Run the following command to start FTP:

firewall-cmd --remove-service=ftp --permanent

Run the following command to add port 80 permanently.
```
firewall-cmd --add-port=80/tcp --permanent
```
Run the following command to view the rules. This command is the same as iptables.
```
iptables -L -n
```
Run the following command to view the PV:
```
man firewall-cmd
```

:Linux operating system How to configure the default firewall for an ECS instance

Overview

Description

Start Firewall

Common Commands

Application scope