之前安装某个包时遇到一个订阅报错，写了一大半，忘记发了，补一下。

yum Package Install on RHEL reports “This system is not registered with an entitlement server”

方法1，

yum install -y https://repo.ius.io/ius-release-el7.rpm

已加载插件：fastestmirror, product-id, search-disabled-repos, subscription-manager,

          : versionlock

This system is not registered with an entitlement server. You can use subscription-manager to register.

ius-release-el7.rpm                                      | 8.2 kB     00:00     

正在检查 /var/tmp/yum-root-xtmc7A/ius-release-el7.rpm: ius-release-2-1.el7.ius.noarch

/var/tmp/yum-root-xtmc7A/ius-release-el7.rpm：不更新已安装的软件包。

错误：无须任何处理

https://unix.stackexchange.com/questions/468629/yum-package-install-on-rhel-reports-this-system-is-not-registered-with-an-entit

Use this command to register, using the credentials you use to access access.redhat.com.

subscription-manager register --username <username> --password <password> --auto-attach

方法2，

对于没有账号的，当然是下面的方法

https://blog.csdn.net/IndexMan/article/details/79570577

https://www.jianshu.com/p/7f22bb72a681

• 查看redhat 7.0系统本身所安装的那些yum软件包

• [root@10-21-2-139 ~]# rpm -qa | grep yum

  yum-plugin-versionlock-1.1.31-54.el7_8.noarch

  yum-3.4.3-161.el7.centos.noarch

  yum-utils-1.1.31-54.el7_8.noarch

  yum-plugin-fastestmirror-1.1.31-50.el7.noarch

  yum-metadata-parser-1.1.4-10.el7.x86_64

rpm -qa | grep yum |xargs rpm -ev --allmatches --nodeps

方法3，

貌似还有一个大招，下次试。