I shut down mongodb server and now I can't start it again with mongod

Question

I use db.shutdownServer() and now want to start it again using mongod, but now it doesn't work, this is the logs

{"t":{"$date":"2022-03-05T08:11:38.545-05:00"},"s":"I",  "c":"NETWORK",  "id":4915701, "ctx":"-","msg":"Initialized wire specification","attr":{"spec":{"incomingExternalClient":{"minWireVersion":0,"maxWireVersion":13},"incomingInternalClient":{"minWireVersion":0,"maxWireVersion":13},"outgoing":{"minWireVersion":0,"maxWireVersion":13},"isInternalClient":true}}}
{"t":{"$date":"2022-03-05T08:11:38.548-05:00"},"s":"I",  "c":"CONTROL",  "id":23285,   "ctx":"main","msg":"Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols 'none'"}
{"t":{"$date":"2022-03-05T08:11:38.548-05:00"},"s":"W",  "c":"ASIO",     "id":22601,   "ctx":"main","msg":"No TransportLayer configured during NetworkInterface startup"}
{"t":{"$date":"2022-03-05T08:11:38.548-05:00"},"s":"I",  "c":"NETWORK",  "id":4648601, "ctx":"main","msg":"Implicit TCP FastOpen unavailable. If TCP FastOpen is required, set tcpFastOpenServer, tcpFastOpenClient, and tcpFastOpenQueueSize."}
{"t":{"$date":"2022-03-05T08:11:38.549-05:00"},"s":"W",  "c":"ASIO",     "id":22601,   "ctx":"main","msg":"No TransportLayer configured during NetworkInterface startup"}
{"t":{"$date":"2022-03-05T08:11:38.549-05:00"},"s":"I",  "c":"REPL",     "id":5123008, "ctx":"main","msg":"Successfully registered PrimaryOnlyService","attr":{"service":"TenantMigrationDonorService","ns":"config.tenantMigrationDonors"}}
{"t":{"$date":"2022-03-05T08:11:38.549-05:00"},"s":"I",  "c":"REPL",     "id":5123008, "ctx":"main","msg":"Successfully registered PrimaryOnlyService","attr":{"service":"TenantMigrationRecipientService","ns":"config.tenantMigrationRecipients"}}
{"t":{"$date":"2022-03-05T08:11:38.549-05:00"},"s":"I",  "c":"CONTROL",  "id":5945603, "ctx":"main","msg":"Multi threading initialized"}
{"t":{"$date":"2022-03-05T08:11:38.550-05:00"},"s":"I",  "c":"CONTROL",  "id":4615611, "ctx":"initandlisten","msg":"MongoDB starting","attr":{"pid":15921,"port":27017,"dbPath":"/data/db","architecture":"64-bit","host":"s-Vostro-3400"}}
{"t":{"$date":"2022-03-05T08:11:38.550-05:00"},"s":"I",  "c":"CONTROL",  "id":23403,   "ctx":"initandlisten","msg":"Build Info","attr":{"buildInfo":{"version":"5.0.6","gitVersion":"212a8dbb47f07427dae194a9c75baec1d81d9259","openSSLVersion":"OpenSSL 1.1.1f  31 Mar 2020","modules":[],"allocator":"tcmalloc","environment":{"distmod":"ubuntu2004","distarch":"x86_64","target_arch":"x86_64"}}}}
{"t":{"$date":"2022-03-05T08:11:38.550-05:00"},"s":"I",  "c":"CONTROL",  "id":51765,   "ctx":"initandlisten","msg":"Operating System","attr":{"os":{"name":"Ubuntu","version":"20.04"}}}
{"t":{"$date":"2022-03-05T08:11:38.550-05:00"},"s":"I",  "c":"CONTROL",  "id":21951,   "ctx":"initandlisten","msg":"Options set by command line","attr":{"options":{}}}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"E",  "c":"CONTROL",  "id":20557,   "ctx":"initandlisten","msg":"DBException in initAndListen, terminating","attr":{"error":"NonExistentPath: Data directory /data/db not found. Create the missing directory or specify another path using (1) the --dbpath command line option, or (2) by adding the 'storage.dbPath' option in the configuration file."}}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"REPL",     "id":4784900, "ctx":"initandlisten","msg":"Stepping down the ReplicationCoordinator for shutdown","attr":{"waitTimeMillis":15000}}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"COMMAND",  "id":4784901, "ctx":"initandlisten","msg":"Shutting down the MirrorMaestro"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"SHARDING", "id":4784902, "ctx":"initandlisten","msg":"Shutting down the WaitForMajorityService"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"NETWORK",  "id":20562,   "ctx":"initandlisten","msg":"Shutdown: going to close listening sockets"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"NETWORK",  "id":4784905, "ctx":"initandlisten","msg":"Shutting down the global connection pool"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":4784906, "ctx":"initandlisten","msg":"Shutting down the FlowControlTicketholder"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"-",        "id":20520,   "ctx":"initandlisten","msg":"Stopping further Flow Control ticket acquisitions."}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"NETWORK",  "id":4784918, "ctx":"initandlisten","msg":"Shutting down the ReplicaSetMonitor"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"SHARDING", "id":4784921, "ctx":"initandlisten","msg":"Shutting down the MigrationUtilExecutor"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"ASIO",     "id":22582,   "ctx":"MigrationUtil-TaskExecutor","msg":"Killing all outstanding egress activity."}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"COMMAND",  "id":4784923, "ctx":"initandlisten","msg":"Shutting down the ServiceEntryPoint"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":4784925, "ctx":"initandlisten","msg":"Shutting down free monitoring"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":4784927, "ctx":"initandlisten","msg":"Shutting down the HealthLog"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":4784928, "ctx":"initandlisten","msg":"Shutting down the TTL monitor"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":4784929, "ctx":"initandlisten","msg":"Acquiring the global lock for shutdown"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"-",        "id":4784931, "ctx":"initandlisten","msg":"Dropping the scope cache for shutdown"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"FTDC",     "id":4784926, "ctx":"initandlisten","msg":"Shutting down full-time data capture"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":20565,   "ctx":"initandlisten","msg":"Now exiting"}
{"t":{"$date":"2022-03-05T08:11:38.551-05:00"},"s":"I",  "c":"CONTROL",  "id":23138,   "ctx":"initandlisten","msg":"Shutting down","attr":{"exitCode":100}}

looks like there is not /data/db folder, but I don't want to lose the previous info, what can I do?

Answer 1

first run:

sudo brew services restart mongodb/brew/mongodb-community

Then run:

sudo brew services start mongodb/brew/mongodb-community

Answer 2

When you run mongod then MongoDB process is started with default parameters, see https://docs.mongodb.com/manual/reference/program/mongod/

However, when you run systemctl start mongod then systemd loads service file /usr/lib/systemd/system/mongod.service (check with systemctl status mongod). When you check this service file then you see that process is started as mongod -f /etc/mongod.conf, i.e. it uses the config file /etc/mongod.conf.

The settings in this config file can be different than mongod default parameters, see What is the default database path for MongoDB?

Note, if you like to customize your Mongo service, then you should not edit service file /usr/lib/systemd/system/mongod.service directly. Instead, make a copy to /etc/systemd/system/mongod.service and modify this copy according to your preferences. Otherwise when you upgrade MongoDB, the installer may revert /usr/lib/systemd/system/mongod.service file to default values.

Folders in this answer apply to Redhat Linux, they may be different on Ubuntu. Have a look at your system documentation.