Centos8 stream如何升级为Centos9 stream

1.输入该命令按回车键：`dnf -y install epel-release`

2.输入该命令按回车键：`dnf -y update`

3.输入该命令按回车键：`dnf -y install rpmconf yum-utils`

4.输入该命令按回车键：`rpmconf -a`，若出现提示输入Y按回车键

5.输入该命令按回车键：`dnf -y remove rpmconf yum-utils epel-release`

6.输入该命令按回车键： rpm -e --nodeps `rpm -qa|grep centos`

7.输入该命令按回车键： rpm -ivh --nodeps --force https://mirrors.aliyun.com/centos-stream/9-stream/BaseOS/x86_64/os/Packages/centos-stream-release-9.0-12.el9.noarch.rpm，  

8.输入该命令按回车键： rpm -ivh --nodeps --force https://mirrors.aliyun.com/centos-stream/9-stream/BaseOS/x86_64/os/Packages/centos-gpg-keys-9.0-12.el9.noarch.rpm  

9.输入该命令按回车键： rpm -ivh --nodeps --force https://mirrors.aliyun.com/centos-stream/9-stream/BaseOS/x86_64/os/Packages/centos-stream-repos-9.0-12.el9.noarch.rpm，  

10.输入该命令按回车键：`dnf clean all`

11.输入该命令按回车键： dnf -y --releasever=9 --allowerasing --setopt=deltarpm=false distro-sync

12.输入该命令按回车键：`rpm --rebuilddb`

13.输入该命令按回车键： rpm -e --nodeps `rpm -qa|grep -i kernel`

14.输入该命令按回车键：`dnf -y install kernel`

15.输入该命令按回车键：`dnf -y install kernel-core`

16.输入该命令按回车键：`dnf -y install shim`

17.输入该命令按回车键：`dnf group install minimal-environment -y`

18.输入该命令按回车键：`dnf -y install epel-release`

19.输入该命令按回车键：`dnf -y install rpmconf yum-utils` 

20.输入该命令按回车键：`dnf -y update`

21.输入该命令按回车键：`rpmconf -a`，若出现提示输入Y按回车键

22.输入该命令按回车键：`grub2-mkconfig -o /boot/grub2/grub.cfg`

23.输入该命令按回车键：`grub2-install /dev/sda`

24.输入该命令按回车键：`echo "PermitRootLogin yes" >> /etc/ssh/sshd_config`

25.输入该命令按回车键重启后再操作连接：`reboot`

26.输入该命令按回车键查看版本：`cat /etc/redhat-release`