How to install yum in centos

Centos 5 i386:

Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/elfutils-libs-0.137-3.el5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/gmp-4.1.4-10.el5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/readline-5.1-3.el5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/python-2.4.3-27.el5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/python-iniparse-0.2.3-4.el5.noarch.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/libxml2-2.6.26-2.1.2.8.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/libxml2-python-2.6.26-2.1.2.8.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/expat-1.95.8-8.2.1.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/python-elementtree-1.2.6-5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/sqlite-3.3.6-5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/python-sqlite-1.1.7-1.2.1.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/elfutils-0.137-3.el5.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/rpm-python-4.4.2.3-18.el5.i386.rpm # (1)
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/m2crypto-0.16-6.el5.6.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/python-urlgrabber-3.1.0-5.el5.noarch.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/yum-metadata-parser-1.1.2-3.el5.centos.i386.rpm
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/yum-3.2.22-20.el5.centos.noarch.rpm (2)
Wget http://mirror.centos.org/centos-5/5/ OS /i386/CentOS/yum-fastestmirror-1.1.16-13.el5.centos.noarch.rpm (2)

Rpm-uvh elfutils-libs-0.137-3.el5.i386.rpm
Rpm-uvh gmp-4.1.4-10.el5.i386.rpm
Rpm-uvh readline-5.1-3.el5.i386.rpm
Rpm-uvh python-2.4.3-27.el5.i386.rpm
Rpm-uvh python-iniparse-0.2.3-4.el5.noarch.rpm
Rpm-uvh libxml2-2.6.26-2.1.2.8.i386.rpm
Rpm-uvh libxml2-python-2.6.26-2.1.2.8.i386.rpm
Rpm-uvh expat-1.95.8-8.2.1.i386.rpm
Rpm-uvh python-elementtree-1.2.6-5.i386.rpm
Rpm-uvh sqlite-3.3.6-5.i386.rpm
Rpm-uvh python-sqlite-1.1.7-1.2.1.i386.rpm
Rpm-uvh elfutils-0.137-3.el5.i386.rpm
Rpm-uvh rpm-python-4.4.2.3-18.el5.i386.rpm # (1)
Rpm-uvh m2crypto-0.16-6.el5.6.i386.rpm
Rpm-uvh python-urlgrabber-3.1.0-5.el5.noarch.rpm
Rpm-uvh yum-metadata-parser-1.1.2-3.el5.centos.i386.rpm
Rpm-import/etc/pki/rpm-GPG/RPM-GPG-KEY-CentOS-5
Rpm-uvh yum-fastestmirror-1.1.16-13.el5.centos.noarch.rpm yum-3.2.22-20.el5.centos.noarch.rpm
Yum-y update
Centos 5 x86_64:

Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/gmp-4.1.4-10.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/readline-5.1-3.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/python-2.4.3-27.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/libxml2-2.6.26-2.1.2.8.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/libxml2-python-2.6.26-2.1.2.8.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/expat-1.95.8-8.2.1.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/python-elementtree-1.2.6-5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/sqlite-3.3.6-5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/python-sqlite-1.1.7-1.2.1.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/elfutils-libelf-0.137-3.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/elfutils-0.137-3.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/rpm-4.4.2.3-18.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/rpm-python-4.4.2.3-18.el5.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/m2crypto-0.16-6.el5.6.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/python-urlgrabber-3.1.0-5.el5.noarch.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/yum-metadata-parser-1.1.2-3.el5.centos.x86_64.rpm
Wget http://mirror.centos.org/centos/5/ OS /x86_64/CentOS/python-iniparse-0.2.3-4.el5.noarch.rpm

Wget ftp://ftp.sunet.se/pub/Linux/distributions/centos/5.5/ OS /x86_64/CentOS/yum-fastestmirror-1.1.16-14.el5.centos.1.noarch.rpm

Wget ftp://ftp.sunet.se/pub/Linux/distributions/centos/5.5/ OS /x86_64/CentOS/yum-3.2.22-26.el5.centos.noarch.rpm

Rpm-uvh gmp-4.1.4-10.el5.x86_64.rpm

Rpm-uvh readline-5.1-3.el5.x86_64.rpm
Rpm-uvh python-2.4.3-27.el5.x86_64.rpm
Rpm-uvh libxml2-2.6.26-2.1.2.8.x86_64.rpm
Rpm-uvh libxml2-python-2.6.26-2.1.2.8.x86_64.rpm
Rpm-uvh expat-1.95.8-8.2.1.x86_64.rpm
Rpm-uvh python-elementtree-1.2.6-5.x86_64.rpm
Rpm-uvh sqlite-3.3.6-5.x86_64.rpm
Rpm-uvh python-sqlite-1.1.7-1.2.1.x86_64.rpm
Rpm-uvh elfutils-libelf-0.137-3.el5.x86_64.rpm
Rpm-uvh elfutils-0.137-3.el5.x86_64.rpm
Rpm-uvh rpm-4.4.2.3-18.el5.x86_64.rpm
Rpm-uvh rpm-python-4.4.2.3-18.el5.x86_64.rpm
Rpm-uvh m2crypto-0.16-6.el5.6.x86_64.rpm
Rpm-uvh python-urlgrabber-3.1.0-5.el5.noarch.rpm
Rpm-uvh yum-metadata-parser-1.1.2-3.el5.centos.x86_64.rpm
Rpm-uvh python-iniparse-0.2.3-4.el5.noarch.rpm
Rpm-import/etc/pki/rpm-GPG/RPM-GPG-KEY-CentOS-5
Rpm-uvh yum-fastestmirror-1.1.16-14.el5.centos.1.noarch.rpm yum-3.2.22-26.el5.centos.noarch.rpm
Yum-y update

If the above file cannot be found, you can find it at http://rpm.pbone.net/, and install it later.
Note: During installation, you can install the SDK at the same time. If you install the SDK at the same time, the dependency may occur.
There is a dependency problem.

Install them together, such
# Rpm-ihv XXX. rpm yyyy. rpm