具体错误栈：
2017-10-11T09:31:12.140+0800 I CONTROL [initandlisten] MongoDB starting : pid=2382 port=27017 dbpath=/data/db 64-bit host=songyuxiangdeMacBook-Pro.local
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] git version: 876ebee8c7dd0e2d992f36a848ff4dc50ee6603e
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] OpenSSL version: OpenSSL 0.9.8zh 14 Jan 2016
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] allocator: system
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] modules: none
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] build environment:
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] distarch: x86_64
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] target_arch: x86_64
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] options: {}
2017-10-11T09:31:12.141+0800 I STORAGE [initandlisten] exception in initAndListen: 29 Data directory /data/db not found., terminating
2017-10-11T09:31:12.141+0800 I NETWORK [initandlisten] shutdown: going to close listening sockets...
2017-10-11T09:31:12.141+0800 I NETWORK [initandlisten] shutdown: going to flush diaglog...
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] now exiting
2017-10-11T09:31:12.141+0800 I CONTROL [initandlisten] shutting down with code:100
解决：
1.安装完 mongodb过后 在安装目录的根目录下 创建两个目录 data log . 进入log 目录 vim mongodb.log
2.进入启动mongoldb 并指定 data的目录
参考我的启动命令。
./mongod --dbpath ../data/
启动mongodb的shell客户端
./mongo
另外 mac下建议使用的 mongodb客户端工具：：robo 3t.
