YUM CRON RHEL7: Configure automatic updates.

Presentation

The yum-cron package provides a convenient way to check for, download and apply updates automatically.

Installation procedure

Install the yum-cron package:

# yum install -y yum-cron

Start the yum-cron service:

# systemctl start yum-cron

By default, the configuration of the yum-cron service is done through two files following exactly the same syntax:

  • /etc/yum/yum-cron.conf defines what is done once every day,
  • /etc/yum/yum-cron-hourly.conf defines what is done once every hour.

Still by default, no action in defined in the /etc/yum/yum-cron-hourly.conf file. Conversely, in the /etc/yum/yum-cron.conf file associated with daily actions, instructions are given to send a message on stdio (which means written into the /var/log/cron file) when any update is available (see update categories below), to download it without applying it.

Configuration syntax

In any of the two configuration files, configuration is defined through the following directives:

  • update_cmd = value specifies the category of upgrade where value can take:
    • default for yum upgrade,
    • security for yum –security upgrade,
    • security-severity:Critical for yum –sec-severity=Critical upgrade,
    • minimal for yum –bugfix upgrade-minimal,
    • minimal-security for yum –security upgrade-minimal,
    • minimal-security-severity:Critical for yum –sec-severity=Critical upgrade-minimal.
  • update_messages = yes/no defines whether a mail is sent when updates from the previously specified category are available.
  • download_updates = yes/no specifies whether these available updates need to be downloaded.
  • apply_updates = yes/no defines whether these available updates need to be applied.
  • random_sleep = 15 specifies the maximum time in minutes to randomly sleep preserving bandwidth and avoiding download storms.
  • emit_via = stdio/email/none defines what kind of message is used: stdio means written into the /var/log/cron file, email causes a mail to be sent, none doesn’t do anything.
  • email_from = root@localhost, email_to = root, email_host = localhost defines respectively when the message is a mail the originator’s email address, the recipient’s email address and the host to which the mail is sent.

Note: As the official CentOS repositories don’t provide any security metadata, update_cmd = default is the only option that works (see here for details). To get these security metadata, you will have to get them through this website. It is also possible to get CentOS security updates through the procedure provided by Casey Labs.

Source: Linuxaria’s website.

0 (0)
Article Rating (No Votes)
Rate this article
Attachments
There are no attachments for this article.
Comments
There are no comments for this article. Be the first to post a comment.
Full Name
Email Address
Security Code Security Code
Related Articles RSS Feed
RHEL: What is "SysRq key" and how to use it
Viewed 1282 times since Sat, Jun 2, 2018
UUIDs and Linux: Everything you ever need to know [Update]
Viewed 486 times since Tue, Jul 17, 2018
How to convert RAW image to VDI and otherwise
Viewed 1147 times since Wed, Oct 3, 2018
Linux - How to perform I/O performance test with dd command
Viewed 528 times since Fri, Jun 8, 2018
How to enable Proxy Settings for Yum Command on RHEL / CentOS Servers
Viewed 766 times since Thu, Jul 19, 2018
Nagrywanie sesji SSH do pliku
Viewed 944 times since Thu, May 24, 2018
LVM: Reduce an existing Logical Volume / Filesystem
Viewed 638 times since Sat, Jun 2, 2018
RHEL: Extending a multipath LUN
Viewed 1058 times since Sun, May 27, 2018
Top 20 OpenSSH Server Best Security Practices ssh linux aix
Viewed 80 times since Fri, May 15, 2020
Inxi: Find System And Hardware Information On Linux
Viewed 823 times since Sat, Jun 2, 2018