Frequently Asked Questions about CentOS 3

1. Who maintains CentOS 3?

The CentOS team, their names are in the The CentOS Development Team section on the About CentOS page.

2. Where are the ISO images?

In the isos directory of the mirrors for centos 3.x, 3 binary CD isos and 3 src isos are available.

See the CentOS Mirrors and the CentOS website for CentOS Downloads.

3. MegaRaid SATA 150-2

Installation driver disk for the LSI MegaRaid 150-2 SATA controller. You can install CentOS 3.3 by starting the installer with "linux dd". When prompted by the installer use the driver disk provided below. Using this method will load the latest megaide.o version 5.6.97 driover. This has been tested on a i686 single processor, however it also has support for SMP i686.

Have fun.

4. What are the differences between centos 3.1, 3.2, and 3.3? Are they all based on Red Hat Enterprise Server (sic Linux) ...

  1. RHEL 3 (and CentOS 3) is based on Red Hat Linux 9.
  2. CentOS 3.1 and CentOS 3.3 are both based on Red Hat Enterprise Linux 3
  3. There is no CentOS 3.2
  4. Red Hat releases updates for their distributions while in active support first in quarterly and thel later semi-annual cycles. CentOS 3.1 is RHEL 3 with update set 1 (U1), CentOS 3.3 is analogous to RHEL 3 with update set 3 (U3), and so forth
  5. The current release is CentOS 3.9 (released July 2007), which is RHEL 3 with update set 9 (U9)

5. How do I migrate a system from WBEL-3 (White Box Enterprise Linux) to CentOS 3?

Note: This process has been tested and reviewed on i686 platforms. I'm looking for a x86_64 tester and someone who wants to try on a i586 class system. {I tested it with x86_64 and i586, both worked ok (hughesjr)} It also works to move from RHEL-3 or TaoLinux-1.0 to CentOS-3.

Migrating from WBEL-3 is a simple process. The procedures here are designed to laterally move your system from WBEL-3 to CentOS 3. The immediate benefits are numerous; timely updates of RHEL errata, developers are reachable, and active community support. Each step below should be run as root and should be entered as a single command in a terminal window. Dynamically sized browser windows may wrap lines.

  1. yum features a "clean" option that will clean up various things in the yum cache directory. This command is optional, but recommended. Optionally Execute: yum clean

  2. This step install the CentOS package signing key. To verify the authenticity of the CentOS 3 package signing key please see this FAQ item.

    • rpm --import
  3. This step installs the CentOS specific -release file; this obsoletes the package whitebox-release. (The whitebox-release package is automatically removed, so you need not concern yourself with it's removal).
    • rpm -Uvh

      Note: Substitute x86_64 for i386 in the above statement to upgrade an x86_64 arch machine

  4. This step installs the CentOS version of yum and a suitable yum.conf file.

    • rpm -Uvh
      rpm -Uvh

      Note: in steps 3 and 4, the version numbers can change for the packages yum, centos-yumconf, centos-yumcache, and centos-release ... so open your web browser to and find the packages yum, centos-yumconf, centos-yumcache, and centos-release for the latest version information if the link doesn't work.

  5. Depending on the version of your WBEL install, your existing yum.conf may have been moved to /etc/yum.conf-SAVE and the CentOS yum.conf placed in /etc or the CentOS specific yum.conf was installed as /etc/yum.conf.rpmnew and your yum.conf was unaltered. If your original yum.conf file was NOT moved save your current yum.conf and replace it with the freshly installed CentOS yum.conf. For now just to get your system working with the default CentOS yum.conf. The following steps will get the CentOS yum.conf accessible by yum.

    • If Necessary:
      cd /etc
      mv yum.conf yum.conf.mysaved
      cp yum.conf.rpmnew yum.conf
      cd -
  6. To verify that your yum.conf file is accurate and to see what packages yum wants to upgrade we strongly encourage you to use yum's list updates feature to display it's intentions before attempting to upgrade your system.

    • NOTE: Version 2.0.x of yum will download many package headers as part of the update process. Yum is not downloading each package, so do not be alarmed by the amount of screen traffic yum is generating. Optionally Execute:

      yum list updates
      yum update
  7. At this point your box is upgraded. A reboot is suggested (to verify the reboot process works and to use any new kernel that was installed). If you were previously using a custom yum.conf file you will want to add your customization back to the current CentOS /etc/yum.conf file. Performing this process will not remove or upgrade any packages where CentOS and Whitebox share the same version number. This allows you to "convert" your box to CentOS and subsequently use CentOS repositories for updates,

We also recommend that you join the CentOS discussion and information mailing list.

6. How can I migrate a system from Red Hat 9 to CentOS 3?

Owl River has created a great Red Hat 9 to CentOS guide. Any efforts to duplicate their work here is futile.

Additional details submitted by Karanbir Singh [z00dax]:

7. '''OLD:''' Why does my recently downloaded CentOS 3.3 x86_64 say it is RC1? Isn't the x86_64 edition released yet?

The ISOs are in fact the release version. No changes were necessary between what was labeled "RC1" and the final release. Respinning ISOs just to change /etc/redhat-release has limited value.

8. I installed CentOS and included mysql (or postgresql), but it (they) didn't get installed. Where are they and how can I install them?

CentOS only installs the clients when you select them as part of the install process. (This is a feature from upstream.)

If you have a properly configured yum.conf you can install either package with:

yum install mysql-server 
(or rh-postgresql-server)

Postgresql on CentOS has a service name of "rhdb" in /etc/rc.d/init.d. (This is a relic of the days when RH was rebranding postgresql RHDB.) The mysql service name is "mysqld"

9. Why does YUM complain about missing a GPG key under CentOS? or I just installed the latest Centos and Yum keeps reporting that the correct GPG key is not installed. How do I install it?

You need to install the CentOS RPM signing key. It is not installed as part of the base system install for security reasons. This provides you the opportunity to validate the key before installing it on your system. RPM has the capacity to retrieve the key from a Centos Mirror:

rpm --import

(as root) will install ('import') the CentOS 3 package signing key for RPM to use to confirm a validly signed package. Please note that it is safer to import the copy of the key from the install ISO media. It is in the root directory of each ISO, as RPM-GPG-KEY, and the same key is present on disc 1 as RPM-GPG-KEY-CentOS-3. The reason this is safer is that a CD is of course an immutable media, and when one verifies ISO MD5SUMs, one is implicitly also verifying the key. As a backstop, this key is as follows:

----BEGIN PGP PUBLIC KEY BLOCK----- Version: GnuPG v1.2.1 (GNU/Linux)

If there is any question as to the validity of the key, please enquire; if a forged key is encountered, please send details, and return contact details to reach you to:

10. Is RHGFS and RHCS available for CentOS-3?

Yes. You can get RHGFS and RHCS for CentOS-3 from here:

Please see this FAQ entry concerning the CentOS Project's relationship with the upstream vendor.

11. How long will CentOS-3 updates be supported?

We intend to support CentOS-3 updates until Oct 31, 2010.

The current plan is this:

Full Updates
During the Full Updates phase, new hardware support will be provided at the discretion of CentOS via Update Sets. Additionally, all available and qualified errata will be provided via Update Sets (or individually {and immediately} for Security level errata.) Update Sets normally will be released 2-4 times per year, with new ISOs released as part of each Update Set. In the 3.x numbering scheme, the .x is the number of the Update Set.
Maintenance Updates
During the Maintenance updates phase, only Security errata and select mission critical bug fixes will be released. There will be few, if any, Update Sets released.

FAQ/CentOS3 (last edited 2010-09-22 19:56:13 by RussHerrold)