Today, we plan to install walle 2.0 according to the official documents http://www.walle-web.io/docs/index.html Step by step

At this step, an error is suddenly reported

yum install -y mariadb-devel gcc gcc-c++ python-devel

 

At first, I wondered if there was a problem with the yum source. Download and load the alicloud source again

cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
wget -P /etc/yum.repos.d/ http://mirrors.aliyun.com/repo/epel-7.repo 
yum clean all  
yum makecache

If you can’t find it, you still report an error

check the python version

# python
Python 2.7.5 (default, Oct 30 2018, 23:45:53) 

It is found that Python has been upgraded to 2.7.5, and the python version required by Yum is 2.6, resulting in an error

modify the yum startup file prefix

# cat /usr/bin/yum
#!/usr/bin/python2.7

It is found that it is useless and there is no backup. Python is directly updated to 2.7.5. The library used by Yum cannot be loaded and the module cannot be loaded

There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

   No module named yum

Please install a package which provides this module, or
verify that the module is installed correctly.

 

Find the information, try to install another version of python2.6.6, and modify the yum startup file, but the module cannot be loaded

reinstall Python and Yum

1. Uninstall existing Python and force the removal of installed programs and their associations

rpm -qa|grep python|xargs rpm -ev --allmatches --nodeps

Force deletion of all residual files

whereis python |xargs rm -frv

2. Uninstall existing yum

rpm -qa|grep yum|xargs rpm -ev --allmatches --nodeps

Force deletion of all residual files

whereis yum |xargs rm -frv

3. Download the RPM package corresponding to the version

wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/libxml2-python-2.9.1-6.el7_2.3.x86_64.rpm

wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-4.11.3-35.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-build-4.11.3-35.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-build-libs-4.11.3-35.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-libs-4.11.3-35.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-sign-4.11.3-35.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/rpm-python-4.11.3-35.el7.x86_64.rpm

wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-2.7.5-76.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-devel-2.7.5-76.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-libs-2.7.5-76.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-pycurl-7.19.0-19.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-setuptools-0.9.8-7.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-urlgrabber-3.10-9.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-iniparse-0.4-9.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-backports-1.0-8.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-backports-ssl_match_hostname-3.5.0.1-1.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-chardet-2.2.1-1.el7_1.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-ipaddress-1.0.16-2.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-kitchen-1.1.1-5.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/python-virtualenv-15.1.0-2.el7.noarch.rpm

wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-3.4.3-161.el7.centos.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-utils-1.1.31-50.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-50.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-plugin-protectbase-1.1.31-50.el7.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/7/os/x86_64/Packages/yum-plugin-aliases-1.1.31-50.el7.noarch.rpm

Install these packages after downloading (- – force forced installation)

rpm -Uvh --force --nodeps --replacepkgs *.rpm

After installing these RPM packages, yum can be used normally. If you still report the following, it means that you haven’t downloaded all the RPM packages

There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

   /usr/lib64/python2.7/site-packages/rpm/_rpm.so: undefined symbol: rpmpkgVerifySi

Please install a package which provides this module, or
verify that the module is installed correctly.

It's possible that the above module doesn't match the
current version of Python, which is:
2.7.5 (default, Apr 11 2018, 07:36:10)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-28)]

If you cannot solve this problem yourself, please go to
the yum faq at:
  http://yum.baseurl.org/wiki/Faq

 

Then press the walle official document to install step by step, and the installation is completed successfully ~:)

say important things three times

Python upgrade is upgraded with the downloaded package. Back up the old version before upgrading

Python upgrade is upgraded with the downloaded package. Back up the old version before upgrading

Python upgrade is upgraded with the downloaded package. Back up the old version before upgrading