centos8平台yum无法安装一些常用软件的解决，如：screen,iftop,nethogs

<h2 style="margin: 10px 0px; padding: 0px; line-height: 1.5; font-size: 21px; font-family: verdana, Arial, Helvetica, sans-serif; text-wrap: wrap; background-color: rgb(255, 255, 255);">一，例如：安装screen时报错:</h2><pre style="margin-top: 0px; margin-bottom: 0px; padding: 0px; transition-duration: 0.2s; transition-property: background, font-size, border-color, border-radius, border-width, padding, margin, color; overflow: auto; font-family: "Courier New", serif; overflow-wrap: break-word;">[root@localhost ~]# yum -y install screen
上次元数据过期检查：0:44:51 前，执行于 2023年10月02日 星期一 01时22分39秒。
未找到匹配的参数: screen
错误：没有任何匹配: screen</pre><h2 style="margin: 10px 0px; padding: 0px; line-height: 1.5; font-size: 21px; font-family: verdana, Arial, Helvetica, sans-serif; text-wrap: wrap; background-color: rgb(255, 255, 255);">二,解决：</h2><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);">centos8上yum源里面没有epel,而screen等一些软件被迁移到了epel源，</p><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);">所以我们需要在centos8上先安装epel源</p><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);">然后就可以安装screen了</p><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);"> </p><pre style="margin-top: 0px; margin-bottom: 0px; padding: 0px; transition-duration: 0.2s; transition-property: background, font-size, border-color, border-radius, border-width, padding, margin, color; overflow: auto; font-family: "Courier New", serif; overflow-wrap: break-word;">[root@localhost liuhongdi]# yum install epel-release</pre><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);"> </p><h2 style="margin: 10px 0px; padding: 0px; line-height: 1.5; font-size: 21px; font-family: verdana, Arial, Helvetica, sans-serif; text-wrap: wrap; background-color: rgb(255, 255, 255);">三,重新尝试安装</h2><pre style="margin-top: 0px; margin-bottom: 0px; padding: 0px; transition-duration: 0.2s; transition-property: background, font-size, border-color, border-radius, border-width, padding, margin, color; overflow: auto; font-family: "Courier New", serif; overflow-wrap: break-word;">[root@localhost liuhongdi]# yum install screen
[root@localhost liuhongdi]# yum install iftop
[root@localhost liuhongdi]# yum install nethogs</pre><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);">已不再提示匹配不到</p><p style="margin: 10px auto; padding: 0px; color: rgb(51, 51, 51); font-family: verdana, Arial, Helvetica, sans-serif; font-size: 14px; text-wrap: wrap; background-color: rgb(255, 255, 255);"> </p><h2 style="margin: 10px 0px; padding: 0px; line-height: 1.5; font-size: 21px; font-family: verdana, Arial, Helvetica, sans-serif; text-wrap: wrap; background-color: rgb(255, 255, 255);">四，查看本地centos的版本</h2><pre style="margin-top: 0px; margin-bottom: 0px; padding: 0px; transition-duration: 0.2s; transition-property: background, font-size, border-color, border-radius, border-width, padding, margin, color; overflow: auto; font-family: "Courier New", serif; overflow-wrap: break-word;">[root@localhost liuhongdi]# cat /etc/redhat-release 
CentOS Linux release 8.1.1911 (Core)</pre><p><br/></p>