[LINUX] Setting to specify the IP allowed for SSH connection

When connecting to the server, the following message is displayed. ..

"There are xxx failed login attempts since the last correct login."

In my case, it was 60,000 times, so I was scared and decided to review the security immediately.

IP address specification permission

Allow connections for specific IPs

Edit the hosts.allow file

$vi /etc/hosts.allow

Original description

all: 127.0.0.1

Added content

sshd: xxx.xx.x.xx

IP address rejection

Deny connections from IPs other than those allowed

Edit the hosts.deny file

$vi /etc/hosts.deny

Original description

all: all

Added content

sshd: ALL

This is a solution. The login failure message is no longer displayed. Rest assured.

Reference site

-When specifying a global IP address ・ What are the hosts.allow file and hosts.deny file