Solve the problem of \\"Failed to start firewalld.service\\" in CentOS7

If we transition from CentOS6 to CentOS7 system, we will find that the original iptables has been replaced by firewalld, and the corresponding command format has also changed slightly. Today, Snail had an error message "FirewallD is not running" when setting up and adding a release port. It should be caused by firewalld not being turned on.

Since it did not start, I executed \\"systemctl start firewalld\\" to start, but the \\"Failed to start firewalld.service: Unit is masked.\\" error appeared again. Continue looking for solutions and enter \\"systemctl unmask firewalld.service\\".

Then start \\"systemctl start firewalld.service\\" to solve the problem without reporting an error.

Recommended site searches: registration network, how to register a domain name, Taiwan server, Taiwan server, registered domain name rental, European server, Ministry of Information Industry registration, ip query detailed address, view ip address, check ip online,