环境：centos7.4   

1、配置YUM源

[root@xiao1 ~]# vim /etc/yum.repos.d/mongodb-org-4.0.repo
[mongodb-org-4.0]
 name = MongoDB Repository
 baseurl = https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/4.0/x86_64/
 gpgcheck = 1
 enabled = 1
 gpgkey = https:// www.mongodb.org/static/pgp/server-4.0.asc

[root@xiao1 ~]# yum clean all

[root@xiao1 ~]# yum list

2、安装

[root@xiao1 ~]# yum -y install mongodb-org

或者

[root@xiao1 ~]# yum install -y mongodb-org-4.0.1 mongodb-org-server-4.0.1 mongodb-org-shell-4.0.1 mongodb-org-mongos-4.0.1 mongodb-org-tools-4.0.1

[root@xiao1 ~]# netstat -anput | grep mongod
 tcp 0 0 127.0.0.1:27017 0.0.0.0:* LISTEN 913/mongod