Welcome to Alibaba Cloud Elastic Compute Service !

[root@liruilong ~]# mdadm
-bash: mdadm: command not found
[root@liruilong ~]# 
[root@liruilong ~]# yum  search mdadm
Loaded plugins: fastestmirror
Repository epel is listed more than once in the configuration
Loading mirror speeds from cached hostfile
 
 
* base: mirrors.cloud.aliyuncs.com
 * extras: mirrors.cloud.aliyuncs.com
 * updates: mirrors.cloud.aliyuncs.com
============================= N/S matched: mdadm ==============================
mdadm.x86_64 : The mdadm program controls Linux md devices (software RAID
             : arrays)

  Name and summary matches only, use 
 
"search all" for everything.
[root@liruilong ~]# yum install -y mdadm.x86_64
Loaded plugins: fastestmirror
Repository epel is listed more than once in the configuration
Loading mirror speeds from cached hostfile
 * base: mirrors.cloud.aliyuncs.com
 * extras: mirrors.cloud.aliyuncs.com
 * updates: mirrors.cloud.aliyuncs.com
Resolving Dependencies
 
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