先使用 yum 安装 redhat-lsb：

yum install -y redhat-lsb

安装完成后，使用 -a 查看

[root@root yum.repos.d]# lsb_release -a
LSB Version:	:core-4.1-amd64:core-4.1-noarch:cxx-4.1-amd64:cxx-4.1-noarch:desktop-4.1-amd64:desktop-4.1-noarch:languages-4.1-amd64:languages-4.1-noarch:printing-4.1-amd64:printing-4.1-noarch
Distributor ID:	CentOS
Description:	CentOS Linux release 8.3.2011
Release:	8.3.2011
Codename:	n/a

redhat-release cat 查看版本号

[root@root yum.repos.d]# cat /etc/redhat-release
CentOS Linux release 8.3.2011

uname 查看内核版本

[root@root6 yum.repos.d]# uname -a
Linux 10-60-71-116 4.18.0-240.1.1.el8_3.x86_64 #1 SMP Thu Nov 19 17:20:08 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux