mongodb启动失败-2

失败提示：

2019-06-21T19:53:08.338+0800 I CONTROL  [initandlisten] ** WARNING: soft rlimits too low. rlimits set to 4096 processes, 65536 files. Number of processes should be at least 32768 : 0.5 times number of files.
2019-06-21T19:53:08.338+0800 I CONTROL  [initandlisten] 
2019-06-21T19:53:08.345+0800 I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/mnt/mongodb/data/diagnostic.data'
2019-06-21T19:53:08.345+0800 I NETWORK  [initandlisten] waiting for connections on port 27017

用systemctl start mongod 启动时报错：

2019-06-27T17:06:48.637+0800 E STORAGE  [initandlisten] WiredTiger error (13) [1561626408:637295][5795:0x7fdf0516fb80], wiredtiger_open: __posix_open_file, 715: /var/lib/mongo/WiredTiger.turtle: handle-open: open: Permission denied
2019-06-27T17:06:48.637+0800 E -        [initandlisten] Assertion: 28595:13: Permission denied src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp 424
2019-06-27T17:06:48.637+0800 I STORAGE  [initandlisten] exception in initAndListen: Location28595: 13: Permission denied, terminating
2019-06-27T17:06:48.637+0800 I NETWORK  [initandlisten] shutdown: going to close listening sockets...
2019-06-27T17:06:48.637+0800 I NETWORK  [initandlisten] removing socket file: /tmp/mongodb-27017.sock
2019-06-27T17:06:48.637+0800 I CONTROL  [initandlisten] now exiting
2019-06-27T17:06:48.637+0800 I CONTROL  [initandlisten] shutting down with code:100

提示：/var/lib/mongo/WiredTiger.turtle: handle-open: open: Permission denied

chmod 777 /var/lib/mongo/WiredTiger.turtle

给完777的权限后又报错：

27726:529978][5897:0x7f5f1e444b80], connection: __posix_open_file, 715: /var/lib/mongo/journal/WiredTigerLog.0000000004: handle-open: open: Permission denied
2019-06-27T17:28:46.532+0800 E -        [initandlisten] Assertion: 28595:13: Permission denied src/mongo/db/storage/wiredtiger/wiredtiger_kv_engine.cpp 424
2019-06-27T17:28:46.532+0800 I STORAGE  [initandlisten] exception in initAndListen: Location28595: 13: Permission denied, terminating

还提示权限问题：

chmod 777 /var/lib/mongo/journal/WiredTigerLog.0000000004

再重启ok了。