


How to check the firewall status in Linux: 1. iptables firewall, check the firewall status, the code is [service iptables status]; 2. Firewall firewall, the code is [firewall-cmd --state].
The operating environment of this tutorial: linux7.3 system, DELL G3 computer.
How to check the firewall status in Linux:
1. iptables firewall
1. Basic operations
# Check the firewall status
service iptables status
# Stop the firewall
service iptables stop
# Start the firewall
service iptables start
# Restart the firewall
service iptables restart
# Permanently close the firewall
chkconfig iptables off
# Restart after permanent shutdown
chkconfig iptables on
2. Open port 80
vim /etc/sysconfig/iptables
# Add the following code
-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
Save and exit and then restart the firewall
service iptables restart
2. Firewall firewall
1. Check the firewall service status
systemctl status firewalld
AppearActive: active (running)
Highlighted means it is started state.
AppearsActive: inactive (dead)
Gray means stop, you can also read the word.
2. Check the status of firewall
firewall-cmd --state
3. Open, restart, close, firewalld.service service
# Open
service firewalld start
# Restart
service firewalld restart
# Close
service firewalld stop
4. Check the firewall rules
firewall-cmd --list-all
5. Query, open and close the port
# Check whether the port is open
firewall-cmd --query-port=8080/tcp
# Open port 80
firewall-cmd --permanent --add-port=80/tcp
# Remove port
firewall-cmd --permanent --remove-port=8080/tcp
#Restart the firewall (restart the firewall after modifying the configuration)
firewall-cmd --reload
Parameter explanation
1. firwall-cmd
: It is a tool provided by Linux to operate the firewall;
2. permanent
: Indicates that it is set to persistent;
3 , add-port
: identifies the added port;
Related learning recommendations: linux video tutorial
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