Do you know what centos and RHEL are? This very advanced application technology will be explained by me. Next I will introduce the infinite fields of centos and RHEL. Just a few days ago, replace the yum Source Address of rhel5.1 with centos, and update yum. After restarting, the original red RHEL will become a blue centos. Therefore, we thought that the two Linux distributions must have a very close relationship. Today, I checked the document and found that RHEL has a very close relationship with centos.
51cto editing recommendation: centos community enterprise operating system
Relationship between centos and RHEL
Centos and RHEL are released in two ways. One is the binary distribution method, and the other is the source code distribution method. No matter which release method you use, you can obtain it for free (for example, download it from the Internet) and release it again. However, if you use their online upgrades (including patches) or consulting services, you must pay for them.
RHEL has always provided source code distribution methods. centos is to re-compile the source code released by RHEL to form a usable binary version. Since the Linux source code is GNU, it is valid from obtaining the source code of centos and RHEL to compiling a new binary. Only RedHat is a trademark, so the trademark of RedHat must be removed from the new release.
Redhat's attitude towards this release is: "We don't really oppose this release. Users who actually pay for it do not pay attention to the system itself, but the commercial services we provide."
Therefore, centos can obtain all RHEL functions and even better software. However, centos does not provide commercial support to users, and of course it is not subject to any commercial responsibilities.
Upgrade from RHEL to centos
After centos and RHEL are installed, if there is no authorization, there is no way to update them online, that is, yum cannot be used. centos and RHEL without yum will be very difficult to use. Therefore, you need to update centos and RHEL to upgrade the centos Yum source.
1. Uninstall RHEL Yum-related packages
List Yum-related packages:
# Rpm-Qa | grep Yum <br/> yum-security-1.0.4-3.el5 <br/> yum-updatesd-3.0.1-5.el5 <br/> yum-rhn-plugin-0.5.2-3.el5 <br/> yum-metadata-parser-1.0-8.fc6 <br/>
Uninstall the related package:
Rpm-e yum-3.0.1-5.el5 -- nodeps <br/> rpm-e yum-updatesd-3.0.1-5.el5 <br/> rpm-e yum-rhn-plugin-0.5.2-3.el5 <br/> rpm-e yum-security-1.0.4-3.el5 <br/> last retained: <br/> # rpm-Qa | grep Yum <br/> yum-metadata-parser-1.0-8.fc6
2. Install the centos Source
First determine the current system version: # uname-
Linux st-71 2.6.18-53.1.13.el5
1 SMP Tue Feb 19 00:19:41 CST 2008 x86_64 x86_64 x86_64 GNU/Linux
Confirm the release version:
# Cat/etc/RedHat-releasered Hat Enterprise Linux Server Release 5.1 (tikanga)
So what is needed is the yum-3.x.el5.centos.5.noarch.rpm of centos 5.1 x86_64
Go to centos official site to find the latest address http://mirror.centos.org/centos/5/ OS/
If the version of RHEL is older, you can find the RPM installation package of yum in the corresponding directory of this address: http://vault.centos.org/to find and download it to idea:
# Wget http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/CentOS/yum-3.0.5-1.el5.centos.5.noarch.rpm
Installation:
# Rpm-IVH yum-3.0.5-1.el5.centos.5.noarch.rpm
Confirm that the installation is successful:
# rpm -qa|grep yum yum-3.0.5-1.el5.centos.5 yum-metadata-parser-1.0-8.fc6
3. Modify CentOS-Base.repo
Go to the yum source configuration Directory: # cd/etc/yum. repos. d/only one file by default: # lsrhel-debuginfo.repo add source configuration for centos: # vi CentOS-Base.repo content is (modified as needed, mainly version (5.1) with system bits (x86_64) need to make appropriate changes ):
[Base] <br/> name = CentOS-5.1-base <br/> baseurl = http://centos.ustc.edu.cn/centos/5.1/ OS /?basearch/ <br/> gpgcheck = 0 <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5
# Released updates <br/> [updates] <br/> name = CentOS-5.1-Updates <br/> baseurl = signature <br/> gpgcheck = 0 <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5
# Packages used/produced in the build but not released <br/> [Addons] <br/> name = CentOS-5.1-Addons <br/> baseurl = signature <br/> gpgcheck = <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5
# Additional packages that may be useful <br/> [extras] <br/> name = CentOS-5.1-extras <br/> baseurl = signature <br/> gpgcheck = 0 <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5 </P> <p> # additional packages that extend functionality of existing packages </P> <p> [centosplus] <br/> name = CentOS-5.1? C plus <br/> baseurl = signature <br/> gpgcheck = 0 <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5 </P> <p> # contrib-packages by centos users <br/> [contrib] <br/> name = CentOS-5.1-contrib <br/> baseurl = http://centos.ustc.edu.cn/centos/5.1/ OS /?basearch/ <br/> gpgcheck = 0 <br/> gpgkey = http://centos.ustc.edu.cn/centos/5.1/ OS /x86_64/RPM-GPG-KEY-CentOS-5