After covering the basics of Yum in my first article, let’s move on to the second part. In this article I’d like to cover some things about keeping your system up to date with Yum on a CentOS 4 system. But these information will also apply with little changes to any other system using Yum like Fedora Core for example.

Let’s begin with a scheduled update of your system: To activate an automatic nightly update, just enter these lines as root:
chkconfig yum on
service yum start


Yum will now check every night for new software versions in your configured Yum repositories and install them. If you didn’t configure any special repositories, at least the normal CentOS update repository is used, so you won’t miss any critical security updates.

But if you configured any 3rd party repositories (like many people do) you should keep the following things in mind: If you add more and more repositories to your Yum configuration, there is a high chance that important system files that were installed from official CentOS repositories (like base and update) are replaced by versions originating from your added 3rd party repositories.
Read the rest of this entry »

20060811: If you will run today up2date on a Red Hat Enterprise Linux 4 system you will notice that there are many updated packages available. This because Red Hat has released the 4th update of RHEL4 and even if we can’t see it yet on the main update page http://www.redhat.com/security/updates/notes/
this new update is already available and if you have set the system to automatically update itself, you might even have the system already updated to RHEL4 update4.

You can quickly check your running version using:

cat /etc/redhat-release
Red Hat Enterprise Linux ES release 4 (Nahant Update 3)

after the update it will look like this:

cat /etc/redhat-release
Red Hat Enterprise Linux ES release 4 (Nahant Update 4)

Even if we can’t see yet the link to the changelog of this update on the redhat update page here is the direct link with details on the changes done in this update:
http://www.redhat.com/docs/manuals/enterprise/RHEL-4-Manual/release-notes/as-x86/RELEASE-NOTES-U4-x86-en.html

In this short post I will show you how you can quickly add a range of IPs on any RedHat based system (Rhel, Centos, Fedora, etc). When you have to add many IPs to a system this can be quite handy and save a lot of time.
Read the rest of this entry »

If you are using RHEL (any version of Redhat from what I know, but if I am wrong please let me know) Fedora or Centos, you don’t have to do anything special. sudo is installed by default and you will already have it on the system.

Read the rest of this entry »