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Hardening & Crash Protecting CentOS + Sentora Server

It often happens that database or dns of a server fails and the sites hosted in it stop working. A server reboot or a start of the service brings things to normal.

This can be stopped by server hardening as attacks are a prime reason for overloading and crashing of services. Hardening is delat in this article.

However, services may stop for internal reasons too. So we will add a cron job that will check for service status and start it if it is crashed due to any reason.

List all services and their status

systemctl list-unit-files (exit by ctrl+c)

Common services

APACHE - httpd

DATABASE - mariadb or mariadb.service

DNS - named or named.service

service named status

Auto Recovery

1. Create a file named.bash


#!/bin/bash
service=mariadb

if (( $(ps -ef | grep -v grep | grep $service | wc -l) != 2 ))
then
echo $(ps -ef | grep -v grep | grep $service | wc -l)
echo "$service is running!!!"
#else
#systemctl start named.service

fi

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