Modify Linux firewall rules

In the company, the fourth time to modify the "firewall rules", tidy up a bit.

Note: The change on the command line is temporary and requires some action to keep the rule forever, making it always effective.

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1, the first step, first look at the server "firewall rules":

Iptables-l

IPTABLES-L-n//Plus one-n displays IP and ports in digital form and looks more comfortable

iptables-l-N--line-number //delete, need to use this, this bar can see each firewall rule number

2. Add a rule:

I am here for the future ES 9200 port, can be accessed by people, so need to add firewall rules:

Iptables-i INPUT 1-p TCP--dport 9200-j ACCEPT//Add (-i) a rule on the first line: TCP port number 9200 allow (ACCEPT) access

3. Delete a firewall rule

iptables-l-N--line-number //delete, need to use this, this bar can see each firewall rule number

iptables-d INPUT 1//delete (-D) First line of firewall rules

4, the most important step, after modifying the firewall rules, you need to save:

Service Iptables Save

Modify Linux firewall rules