If you nead, automated certificate expiration checks on CentOS Linux

One important part of using SSL is to keep track of expiration dates on certificates. Most client software will rightfully refuse to connect to a server that presents an expired certificate, resulting in interrupted services. For CentOS and other RHEL based distributions, the crypto-utils package contains a very useful utility called certwatch, which can be used to detect whether a certificate will expire in the near future. Read More

How To Use Cron To Automate Tasks

Installation

Almost all distros have a form of cron installed by default. However, if you’re using a system that doesn’t have it installed, you can install it with the following commands:
For Ubuntu/Debian:

apt-get update
apt-get install cron

For Cent OS/Red Hat Linux:

yum update
yum install vixie-cron crontabs

You’ll need to make sure it runs in the background too:

chkconfig crond on
service crond start

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