Initial Settings : Update System

The package management tool DNF (Dandified YUM) has been set default on RHEL 8 / CentOS 8.

However, [yum] command is also located as a link to [dnf], so it's possbile to use [yum] or [dnf] with the same usage. Actually, the official documents on RedHat gives examples with [yum] command for RHEL 8.

(the documents on this site gives examples with [dnf] command)

[1]. [yum] and [dnf] are linked to [dnf-3] command.

[root@dlp ~]# which yum

/usr/bin/yum

[root@dlp ~]# ll /usr/bin/yum

lrwxrwxrwx. 1 root root 5 May 14 04:34 /usr/bin/yum -> dnf-3

[root@dlp ~]# which dnf

/usr/bin/dnf

[root@dlp ~]# ll /usr/bin/dnf

lrwxrwxrwx. 1 root root 5 May 14 04:34 /usr/bin/dnf -> dnf-3

[root@dlp ~]# ll /usr/bin/dnf-3

-rwxr-xr-x. 1 root root 1954 May 14 04:34 /usr/bin/dnf-3

# installed [yum] package

[root@dlp ~]# rpm -q yum

yum-4.0.9.2-5.el8.noarch

[root@dlp ~]# rpm -ql yum

/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 May 14 04:34 /etc/yum.conf -> dnf/dnf.conf

[root@dlp ~]# ll /etc/yum/vars

lrwxrwxrwx. 1 root root 11 May 14 04:34 /etc/yum/vars -> ../dnf/vars

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

[root@dlp ~]# dnf -y upgrade

CentOS-8 - AppStream 2.5 kB/s | 4.3 kB 00:01

CentOS-8 - Base 2.4 kB/s | 3.8 kB 00:01

CentOS-8 - Extras 1.1 kB/s | 1.5 kB 00:01

Dependencies resolved.

.....

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