我使用以下命令安装了 mongoDB：
wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add -
echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list
sudo apt-get update
sudo apt-get install -y mongodb-org
echo "mongodb-org hold" | sudo dpkg --set-selections
echo "mongodb-org-server hold" | sudo dpkg --set-selections
echo "mongodb-org-shell hold" | sudo dpkg --set-selections
echo "mongodb-org-mongos hold" | sudo dpkg --set-selections
echo "mongodb-org-tools hold" | sudo dpkg --set-selections
正如官方网站所述。
现在当我sudo mongod：
{"t":{"$date":"2020-10-02T00:21:47.990+05:30"},"s":"I", "c":"CONTROL", "id":23285, "ctx":"main","msg":"Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols 'none'"}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"W", "c":"ASIO", "id":22601, "ctx":"main","msg":"No TransportLayer configured during NetworkInterface startup"}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"I", "c":"NETWORK", "id":4648601, "ctx":"main","msg":"Implicit TCP FastOpen unavailable. If TCP FastOpen is required, set tcpFastOpenServer, tcpFastOpenClient, and tcpFastOpenQueueSize."}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"I", "c":"STORAGE", "id":4615611, "ctx":"initandlisten","msg":"MongoDB starting","attr":{"pid":71748,"port":27017,"dbPath":"/data/db","architecture":"64-bit","host":"Monster"}}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"I", "c":"CONTROL", "id":23403, "ctx":"initandlisten","msg":"Build Info","attr":{"buildInfo":{"version":"4.4.1","gitVersion":"ad91a93a5a31e175f5cbf8c69561e788bbc55ce1","openSSLVersion":"OpenSSL 1.1.1f 31 Mar 2020","modules":[],"allocator":"tcmalloc","environment":{"distmod":"ubuntu2004","distarch":"x86_64","target_arch":"x86_64"}}}}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"I", "c":"CONTROL", "id":51765, "ctx":"initandlisten","msg":"Operating System","attr":{"os":{"name":"Ubuntu","version":"20.04"}}}
{"t":{"$date":"2020-10-02T00:21:47.992+05:30"},"s":"I", "c":"CONTROL", "id":21951, "ctx":"initandlisten","msg":"Options set by command line","attr":{"options":{}}}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"E", "c":"STORAGE", "id":20557, "ctx":"initandlisten","msg":"DBException in initAndListen, terminating","attr":{"error":"NonExistentPath: Data directory /data/db not found. Create the missing directory or specify another path using (1) the --dbpath command line option, or (2) by adding the 'storage.dbPath' option in the configuration file."}}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"REPL", "id":4784900, "ctx":"initandlisten","msg":"Stepping down the ReplicationCoordinator for shutdown","attr":{"waitTimeMillis":10000}}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"COMMAND", "id":4784901, "ctx":"initandlisten","msg":"Shutting down the MirrorMaestro"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"SHARDING", "id":4784902, "ctx":"initandlisten","msg":"Shutting down the WaitForMajorityService"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"NETWORK", "id":20562, "ctx":"initandlisten","msg":"Shutdown: going to close listening sockets"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"NETWORK", "id":4784905, "ctx":"initandlisten","msg":"Shutting down the global connection pool"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"STORAGE", "id":4784906, "ctx":"initandlisten","msg":"Shutting down the FlowControlTicketholder"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"-", "id":20520, "ctx":"initandlisten","msg":"Stopping further Flow Control ticket acquisitions."}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"NETWORK", "id":4784918, "ctx":"initandlisten","msg":"Shutting down the ReplicaSetMonitor"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"SHARDING", "id":4784921, "ctx":"initandlisten","msg":"Shutting down the MigrationUtilExecutor"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"CONTROL", "id":4784925, "ctx":"initandlisten","msg":"Shutting down free monitoring"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"FTDC", "id":4784926, "ctx":"initandlisten","msg":"Shutting down full-time data capture"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"STORAGE", "id":4784927, "ctx":"initandlisten","msg":"Shutting down the HealthLog"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"STORAGE", "id":4784929, "ctx":"initandlisten","msg":"Acquiring the global lock for shutdown"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"-", "id":4784931, "ctx":"initandlisten","msg":"Dropping the scope cache for shutdown"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"CONTROL", "id":20565, "ctx":"initandlisten","msg":"Now exiting"}
{"t":{"$date":"2020-10-02T00:21:47.993+05:30"},"s":"I", "c":"CONTROL", "id":23138, "ctx":"initandlisten","msg":"Shutting down","attr":{"exitCode":100}}
并mongo返回：
MongoDB shell version v4.4.1
connecting to: mongodb://127.0.0.1:27017/?compressors=disabled&gssapiServiceName=mongodb
Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:374:17
@(connect):2:6
exception: connect failed
exiting with code 1
我也尝试了所有排列
sudo systemctl enable mongod
sudo service mongod restart
sudo service mongod start
但sudo service mongod status给出：
● mongod.service - MongoDB Database Server
Loaded: loaded (/lib/systemd/system/mongod.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Fri 2020-10-02 00:12:32 IST; 15min ago
Docs: https://docs.mongodb.org/manual
Main PID: 70418 (code=exited, status=14)
Oct 02 00:12:32 Monster systemd[1]: Started MongoDB Database Server.
Oct 02 00:12:32 Monster systemd[1]: mongod.service: Main process exited, code=exited, status=14/n/a
Oct 02 00:12:32 Monster systemd[1]: mongod.service: Failed with result 'exit-code'.
Oct 02 00:20:27 Monster systemd[1]: /lib/systemd/system/mongod.service:11: PIDFile= references a path below legacy directory /var/run/, updating /var/run/mongodb/mongod.pid → /run/mongodb/mongod.pid; please upd>
Oct 02 00:21:54 Monster systemd[1]: /lib/systemd/system/mongod.service:11: PIDFile= references a path below legacy directory /var/run/, updating /var/run/mongodb/mongod.pid → /run/mongodb/mongod.pid; please upd>
lines 1-11/11 (END)
我没有 /etc/systemd/system/mongodb.service文件，因此我创建了一个包含以下内容的文件：
GNU nano 4.8
systemd/system/mongodb.service
[Unit]
Description=High-performance, schema-free document-oriented database
After=network.target
[Service]
User=mongodb
ExecStart=/usr/bin/mongod --quiet --config /etc/mongod.conf
[Install]
WantedBy=multi-user.target
我没有心情重新安装 mongoDb，因为尝试了所有可用的解决方案都没有用。所以如果有人知道这一点，请帮助我和其他数千名将面临这个问题的开发人员。
编辑：甚至尝试删除包并重新安装，但无济于事。再次出现完全相同的错误。
答案1
创建目录 /data/db 并授予 MongoDB 用户权限，以便 MongoDB 可以访问它。要创建目录：
sudo mkdir -p /data/db
更改所有者：
sudo chown -R $USER /data/db
答案2
我刚刚在其他地方找到了这个。最后一个选项对我有用，在 Ubuntu 20.04 中的 DigitalOcean droplet 中...
如何在 ubuntu 中重新启动 mongodb 服务器#它将重新启动正在运行的 mongodb 服务器：
sudo systemctl restart mongodb
如何在 ubuntu 中停止 mongodb 服务器，它将停止运行 mongodb 服务器：
sudo systemctl stop mongodb
启动和停止 mongodb 服务 ubuntu：
sudo systemctl start mongod sudo systemctl stop mongod
mongodb重启命令ubuntu：
sudo systemctl restart mongod
ubuntu 启动mongodb
sudo mongod --fork --config /etc/mongod.conf