sudo apt-get install -y mongodb-org

MongoDB shell version v3.6.4
connecting to: mongodb://127.0.0.1:27017
2018-04-20T12:02:10.947+0530 W NETWORK  [thread1] Failed to connect to 127.0.0.1:27017, in(checking socket for error after poll), reason: Connection refused
2018-04-20T12:02:10.999+0530 E QUERY    [thread1] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed :
connect@src/mongo/shell/mongo.js:251:13
@(connect):1:6
exception: connect failed

● mongod.service - High-performance, schema-free document-oriented database
    Loaded: loaded (/lib/systemd/system/mongod.service; disabled; vendor preset:
   Active: failed (Result: exit-code) since Fri 2018-04-20 12:04:50 IST; 37s ago
     Docs: https://docs.mongodb.org/manual
  Process: 28034 ExecStart=/usr/bin/mongod --config /etc/mongod.conf (code=exite
 Main PID: 28034 (code=exited, status=217/USER)

Apr 20 12:04:50 Inspiron-N5010 systemd[1]: Started High-performance, schema-free
Apr 20 12:04:50 Inspiron-N5010 systemd[1]: mongod.service: Main process exited,
Apr 20 12:04:50 Inspiron-N5010 systemd[1]: mongod.service: Unit entered failed s
Apr 20 12:04:50 Inspiron-N5010 systemd[1]: mongod.service: Failed with result 'e
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