GUIDE TO UPGRADE CENTOS 7 TO CENTOS 8
Check Information
Use the check version CentOS uname-A or cat/etc/redhat-release command
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Step 1 Install the EPEL repository
Yum Install Epel-Release-y
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Install Yum-utils
Install Yum install yum-utils
Install the rpmconf configuration RPM Package
# yum Install rpmconf # rpmconf-A
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Run the command rpmconf-A-> select N means Update the nsswitch. conf file to keep the current version
Next step we clean
# Package-cleanup--Leaves # Package-cleanup--orphans
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Step 3: Install DNF Centos 7
Yum install DNF
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Remove Management Packs with the command
#dnf-y remove yum yum-metadata-parser # RM-Rf/etc/yum
Step 4: Upgrade Centos 7 to Centos 8
with DNF Upgrade not using yum command
# DNF Upgrade
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Steps to install CentOS 8 packages using DNF command
DNF-y Upgrade http://mirror.bytemark.co.uk/centos/8/BaseOS/x86_64/os/Packages/centos-release-8.0-0.1905.0.9.el8.x86_64.rpm
Update EPEL Repo
DNF-y Upgrade https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
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After the update is complete we clear DNF
DNF Clean All
Delete always old kernel Centos 7
RPM-E 'rpm-Q kernel'
Always delete conflicting packages if available
# RPM-E--nodeps sysvinit-Tools
Launch Run Cenots 8
# DNF-y--releasever = 8--allowerasing--setopt = deltarpm = False distro-sync
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Step 5: Install new Kernel OS Centos 8
# DNF-y install kernel-core
Set the core.
DNF-y groupupdate "Core" "Minimal Install"
Check version for Success
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I Wish you success