Update Centos System

After CentOS Stream Server has been a production System, maybe it's difficult to update System, but at least after Installing, Update CentOS Stream Server to the latest.

1. For commands to updating System, it's possible to use [yum] or [dnf], but both are the link to [dnf-3], so you may use [yum] or [dnf] as you like.

[root@dlp ~]# which yum
/usr/bin/yum
[root@dlp ~]# ll /usr/bin/yum
lrwxrwxrwx. 1 root root 5 Aug 5 2020 /usr/bin/yum -> dnf-3
[root@dlp ~]# which dnf
/usr/bin/dnf
[root@dlp ~]# ll /usr/bin/dnf
lrwxrwxrwx. 1 root root 5 Aug 5 2020 /usr/bin/dnf -> dnf-3
[root@dlp ~]# ll /usr/bin/dnf-3
-rwxr-xr-x. 1 root root 1954 Aug 5 2020 /usr/bin/dnf-3
# installed [yum] package
[root@dlp ~]# rpm -q yum
yum-4.2.23-4.el8.noarch
[root@dlp ~]# rpm -ql yum
/etc/dnf/protected.d/yum.conf
/etc/yum.conf
/etc/yum/pluginconf.d
/etc/yum/protected.d
/etc/yum/vars
/usr/bin/yum
/usr/share/man/man1/yum-aliases.1.gz
/usr/share/man/man5/yum.conf.5.gz
/usr/share/man/man8/yum-shell.8.gz
/usr/share/man/man8/yum.8.gz
# included files are all links to [dnf]
[root@dlp ~]# ll /etc/yum.conf
lrwxrwxrwx. 1 root root 12 Aug 5 2020 /etc/yum.conf -> dnf/dnf.conf
[root@dlp ~]# ll /etc/yum/vars
lrwxrwxrwx. 1 root root 11 Aug 5 2020 /etc/yum/vars -> ../dnf/vars

2. Update CentOS Stream Server like follows.

[root@dlp ~]# dnf -y upgrade
Last metadata expiration check: 0:50:40 ago on Fri 19 Feb 2021 12:00:48 PM JST.
Dependencies resolved.
============================================================================================================
 Package                                  Arch    Version                                   Repo        Size
============================================================================================================
Installing:
 kernel                                   x86_64  4.18.0-277.el8                            baseos     5.5 M
 kernel-core                              x86_64  4.18.0-277.el8                            baseos      35 M
 kernel-modules                           x86_64  4.18.0-277.el8                            baseos      28 M
.....
.....