Summary of Common commands in Linux (7) Security Settings and Common commands in linux

Summary of Common commands in Linux (7) Security Settings and Common commands in linux

Security Settings
Category	Command	Option	Annotation
Security Policy Selinux	Setenforce	Number (0, 1)	Set selinux status, 0 closed, 1 Enabled
	Getenforce		Displays the current selinux status. enforcing indicates enabled, and permissive indicates disabled.
Firewall	Iptables	Three tables: filter, nat, and mangle	For example, iptables-a input-p tcp -- dport 22-j ACCEPT
		-A (-I,-D)	Add (insert, delete) a rule
		INPUT (OUTPUT, FORWARD)	Chain name
		-S	Source Address
		-P	Protocol (tcp, udp, icmp)
		-- Sport/-- dport	Followed by the source port/Target Port
		-D	Followed by the destination IP address
		-J	Followed by the action after the rule is triggered. DROP/REJECT/ACCEPT
Shutdown/restart	Shutdown	[Option]	Shutdown
		-T	Number of seconds after Shutdown
		-R	Restart after shutdown at the specified time
		-H	Shutdown at specified time
		-C	Cancel ongoing shutdown
	Halt	[Option]	Pending
		-P	Shutdown
	Reboot		Restart = shutdown-r now