Tutorial on upgrading from Centos7 to Centos8 (with pictures and text)

If you upgrade in a formal environment, please back up your data and important configurations! Because the upgrade will cause some applications to be uninstalled.

1. Install the epel source

yum -y install epel-release

2. Install rpmconf and yum-utils

yum -y install rpmconf yum-utils

3. Execute rpmconf. If some prompts appear, please enter Y and press Enter to continue. If no prompts appear, continue to step 4.

rpmconf -a

4. Install dnf

yum -y install dnf

5. Remove yum and yum-metadata-parser

dnf -y remove yum yum-metadata-parser

6. Delete the /etc/yum directory

rm -rf /etc/yum

7. Install Centos8 source and upgrade epel source

dnf -y upgrade
dnf -y upgrade http://mirrors.163.com/centos/8.0.1905/BaseOS/x86_64/os/Packages/centos-release-8.0-0.1905.0.9.el8.x86_64.rpm
dnf -y upgrade https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
dnf clean all 

8. Uninstall the kernel of centos7

rpm -e --nodeps `rpm -q kernel`

9. Upgrade to centos8. This step will generally report an error. If there is no error, please proceed to step 10.

dnf -y --releasever=8 --allowerasing --setopt=deltarpm=false distro-sync 

After finding the error, first uninstall the package name similar to the one after from package in the figure

rpm -e --nodeps sysvinit-tools-2.88-14.dsf.el7.x86_64
rpm -e --nodeps python-inotify-0.9.4-4.el7.noarch
rpm -e --nodeps adwaita-qt5-1.0-1.el7.x86_64
rpm -e --nodeps pycairo-1.8.10-8.el7.x86_64 

After uninstalling, perform the upgrade again

dnf -y --releasever=8 --allowerasing --setopt=deltarpm=false distro-sync

10. Execute rpmconf, the following interface will appear, just keep entering Y and pressing Enter

rpmconf -a

11. Restart the machine

reboot

Summarize

The above is the tutorial on upgrading from Centos7 to Centos8 introduced by the editor. I hope it will be helpful to everyone. If you have any questions, please leave me a message and the editor will reply to you in time. I would also like to thank everyone for their support of the 123WORDPRESS.COM website!
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