1、导入包管理系统使用的公钥 
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 0C49F3730359A14518585931BC711F9BA15703C6
2、为mongodb创建一个源文件 ubuntu14.04: 
echo "deb [ arch=amd64 ] http://mirrors.aliyun.com/mongodb/apt/debian wheezy/mongodb-org/3.4 main" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.4.list

echo "deb [ arch=amd64 ] http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.4.list
ubuntu16.04: 
echo "deb [ arch=amd64,arm64 ] http://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.4.list
3、重新加载本地数据库 
sudo apt-get update
4、安装mongodb 
sudo apt-get install -y mongodb-org
官方参考地址：https://docs.mongodb.com/v3.4/tutorial/install-mongodb-on-ubuntu/