CentOSのversion確認
ssh hostA [root@hostA ~]# cat /etc/redhat-release CentOS release 6.5 (Final)
ssh hostB [root@hostB ~]# cat /etc/redhat-release CentOS Linux release 7.5.1804 (Core)
ssh hostA [root@hostA ~]# cat /etc/redhat-release CentOS release 6.5 (Final)
ssh hostB [root@hostB ~]# cat /etc/redhat-release CentOS Linux release 7.5.1804 (Core)