title: Mongo-Express started by Docker-Compose causing Error [MongoError]: failed to connect to server [mongo:27017] on first connect
body: <p>Scenario: I want to start both Mongo and Mongo-Express from same docker-compose.</p>
  
  <p>I have no issue starting only mongodb from docker-compose. The issue raises when I try to link Mongo-Express to Mongo DB Service.</p>
  
  <p>I am not sure if I am missing either some configuration in docker-compose or in my mongo-express settup. I am not expecting the issue being part of Mongo settup. BTW, I pasted bellow whole docker-compose and and its output.</p>
  
  <p>From bellow logs I can see there is no issue raising Mongo. There is some issue when mongo-express tries connect to Mongo service probably because I didn't settup link properly. On top of that, my Spring Webflux is connecting succesfully to Mongo DB with bellow propertis. The issue is really limited to mongo-express reaching mongodb.</p>
  
  <p>application.yml that allows Spring Data (spring-boot-starter-data-mongodb-reactive) connects successfuly to such MongoDb</p>
  
  <pre><code>spring:
    data:
      mongodb:
        host: 192.168.99.100
        port:  27017
        database: demodb
        authentication-database: admin
        username: root
        password: rootpassword
  </code></pre>
  
  <p>docker-compose.yml</p>
  
  <pre><code>version: '3.7'
  
  services:
    mongo-express:
      image: mongo-express
      ports:
        - 8081:8081
      environment:
        ME_CONFIG_BASICAUTH_USERNAME: admin
        ME_CONFIG_BASICAUTH_PASSWORD: q
        ME_CONFIG_MONGODB_PORT: 27017
        ME_CONFIG_MONGODB_ADMINUSERNAME: root
        ME_CONFIG_MONGODB_ADMINPASSWORD: rootpassword
      links:
        - mongo-db
      networks:
        - mongo-compose-network
  
    mongo-db:
      image: mongo:latest
      environment:
        MONGO_INITDB_DATABASE: demodb  
        MONGO_INITDB_ROOT_USERNAME: root
        MONGO_INITDB_ROOT_PASSWORD: rootpassword
      ports:
        - "27017:27017"
      volumes:
        - mongodb_data_container:/data/db
      networks:
        - mongo-compose-network
  
  networks: 
      mongo-compose-network:
        driver: bridge
  
  volumes:
    mongodb_data_container:       
  </code></pre>
  
  <p>output</p>
  
  <pre><code>PS C:\Dockers\mongodb\express&gt; docker-compose up
  Creating express_mongo_1 ... done                                                                                                      Creating express_mongo-express_1 ... done                                                                                              Attaching to express_mongo_1, express_mongo-express_1
  mongo_1          | 2020-03-18T21:49:37.366+0000 I  CONTROL  [main] Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols 'none'
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] MongoDB starting : pid=1 port=27017 dbpath=/data/db 64-bit host=8c1f22435085
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] db version v4.2.3
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] git version: 6874650b362138df74be53d366bbefc321ea32d4
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.1.1  11 Sep 2018
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] allocator: tcmalloc
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] modules: none
  mongo-express_1  | Waiting for mongo:27017...
  mongo_1          | 2020-03-18T21:49:37.370+0000 I  CONTROL  [initandlisten] build environment:
  mongo_1          | 2020-03-18T21:49:37.371+0000 I  CONTROL  [initandlisten]     distmod: ubuntu1804
  mongo_1          | 2020-03-18T21:49:37.371+0000 I  CONTROL  [initandlisten]     distarch: x86_64
  mongo_1          | 2020-03-18T21:49:37.371+0000 I  CONTROL  [initandlisten]     target_arch: x86_64
  mongo_1          | 2020-03-18T21:49:37.371+0000 I  CONTROL  [initandlisten] options: { net: { bindIp: "*" }, security: { authorization: "enabled" } }
  mongo-express_1  | /docker-entrypoint.sh: connect: Connection refused
  mongo_1          | 2020-03-18T21:49:37.373+0000 I  STORAGE  [initandlisten] Detected data files in /data/db created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
  mongo_1          | 2020-03-18T21:49:37.373+0000 I  STORAGE  [initandlisten]
  mongo_1          | 2020-03-18T21:49:37.373+0000 I  STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine
  mongo_1          | 2020-03-18T21:49:37.373+0000 I  STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem
  mongo_1          | 2020-03-18T21:49:37.374+0000 I  STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=486M,cache_overflow=(file_max=0M),session_max=33000,eviction=(threads_min=4,threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000,close_scan_interval=10,close_handle_minimum=250),statistics_log=(wait=0),verbose=[recovery_progress,checkpoint_progress],
  mongo_1          | 2020-03-18T21:49:38.229+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:229680][1:0x7f9df38f3b00], txn-recover: Recovering log 5 through 6
  mongo_1          | 2020-03-18T21:49:38.261+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:261407][1:0x7f9df38f3b00], txn-recover: Recovering log 6 through 6
  mongo_1          | 2020-03-18T21:49:38.313+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:313791][1:0x7f9df38f3b00], txn-recover: Main recovery loop: starting at 5/6144 to 6/256
  mongo_1          | 2020-03-18T21:49:38.378+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:378014][1:0x7f9df38f3b00], txn-recover: Recovering log 5 through 6
  mongo_1          | 2020-03-18T21:49:38.448+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:448927][1:0x7f9df38f3b00], txn-recover: Recovering log 6 through 6
  mongo_1          | 2020-03-18T21:49:38.480+0000 I  STORAGE  [initandlisten] WiredTiger message [1584568178:480668][1:0x7f9df38f3b00], txn-recover: Set global recovery timestamp: (0, 0)
  mongo_1          | 2020-03-18T21:49:38.505+0000 I  RECOVERY [initandlisten] WiredTiger recoveryTimestamp. Ts: Timestamp(0, 0)
  mongo_1          | 2020-03-18T21:49:38.519+0000 I  STORAGE  [initandlisten] Timestamp monitor starting
  mongo_1          | 2020-03-18T21:49:38.530+0000 I  SHARDING [initandlisten] Marking collection local.system.replset as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.535+0000 I  STORAGE  [initandlisten] Flow Control is enabled on this deployment.
  mongo_1          | 2020-03-18T21:49:38.535+0000 I  SHARDING [initandlisten] Marking collection admin.system.roles as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.536+0000 I  SHARDING [initandlisten] Marking collection admin.system.version as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.541+0000 I  SHARDING [initandlisten] Marking collection local.startup_log as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.542+0000 I  FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/data/db/diagnostic.data'
  mongo_1          | 2020-03-18T21:49:38.544+0000 I  SHARDING [LogicalSessionCacheRefresh] Marking collection config.system.sessions as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.545+0000 I  SHARDING [LogicalSessionCacheReap] Marking collection config.transactions as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:38.546+0000 I  NETWORK  [listener] Listening on /tmp/mongodb-27017.sock
  mongo_1          | 2020-03-18T21:49:38.546+0000 I  NETWORK  [listener] Listening on 0.0.0.0
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Connection refused
  mongo_1          | 2020-03-18T21:49:38.546+0000 I  NETWORK  [listener] waiting for connections on port 27017
  mongo_1          | 2020-03-18T21:49:38.863+0000 I  NETWORK  [listener] connection accepted from 172.22.0.3:53802 #1 (1 connection now open)
  mongo_1          | 2020-03-18T21:49:38.864+0000 I  NETWORK  [conn1] end connection 172.22.0.3:53802 (0 connections now open)
  mongo-express_1  | Wed Mar 18 21:49:38 UTC 2020 retrying to connect to mongo:27017 (2/5)
  mongo-express_1  | Welcome to mongo-express
  mongo-express_1  | ------------------------
  mongo-express_1  |
  mongo-express_1  |
  mongo-express_1  | Mongo Express server listening at http://0.0.0.0:8081
  mongo_1          | 2020-03-18T21:49:39.000+0000 I  SHARDING [ftdc] Marking collection local.oplog.rs as collection version: &lt;unsharded&gt;
  mongo_1          | 2020-03-18T21:49:39.338+0000 I  NETWORK  [listener] connection accepted from 172.22.0.3:53804 #2 (1 connection now open)
  mongo-express_1  | Server is open to allow connections from anyone (0.0.0.0)
  mongo_1          | 2020-03-18T21:49:39.344+0000 I  NETWORK  [conn2] received client metadata from 172.22.0.3:53804 conn2: { driver: { name: "nodejs", version: "2.2.24" }, os: { type: "Linux", name: "linux", architecture: "x64", version: "4.14.154-boot2docker" }, platform: "Node.js v12.16.1, LE, mongodb-core: 2.1.8" }
  mongo_1          | 2020-03-18T21:49:39.350+0000 I  SHARDING [conn2] Marking collection admin.system.users as collection version: &lt;unsharded&gt;
  mongo-express_1  | Database connected
  mongo_1          | 2020-03-18T21:49:39.809+0000 I  ACCESS   [conn2] Successfully authenticated as principal root on admin from client 172.22.0.3:53804
  mongo_1          | 2020-03-18T21:49:39.816+0000 I  NETWORK  [listener] connection accepted from 172.22.0.3:53806 #3 (2 connections now open)
  mongo_1          | 2020-03-18T21:49:39.821+0000 I  NETWORK  [listener] connection accepted from 192.168.99.1:51536 #4 (3 connections now open)
  mongo_1          | 2020-03-18T21:49:39.822+0000 I  NETWORK  [conn4] received client metadata from 192.168.99.1:51536 conn4: { driver: { name: "mongo-java-driver|legacy", version: "3.11.2" }, os: { type: "Windows", name: "Windows 10", architecture: "amd64", version: "10.0" }, platform: "Java/Oracle Corporation/11.0.6+8-LTS" }
  mongo_1          | 2020-03-18T21:49:39.927+0000 I  ACCESS   [conn3] Successfully authenticated as principal root on admin from client 172.22.0.3:53806
  mongo_1          | 2020-03-18T21:49:40.759+0000 I  NETWORK  [listener] connection accepted from 192.168.99.1:51537 #5 (4 connections now open)
  mongo_1          | 2020-03-18T21:49:40.761+0000 I  NETWORK  [conn5] received client metadata from 192.168.99.1:51537 conn5: { driver: { name: "mongo-java-driver|async|mongo-java-driver-reactivestreams", version: "3.11.2|1.12.0" }, os: { type: "Windows", name: "Windows 10", architecture: "amd64", version: "10.0" }, platform: "Java/Oracle Corporation/11.0.6+8-LTS" }
  mongo_1          | 2020-03-18T21:50:39.101+0000 I  NETWORK  [conn4] end connection 192.168.99.1:51536 (3 connections now open)
  mongo_1          | 2020-03-18T21:50:39.102+0000 I  NETWORK  [conn5] end connection 192.168.99.1:51537 (2 connections now open)
  mongo_1          | 2020-03-18T21:50:57.344+0000 I  NETWORK  [listener] connection accepted from 192.168.99.1:51576 #6 (3 connections now open)
  mongo_1          | 2020-03-18T21:50:57.355+0000 I  NETWORK  [conn6] received client metadata from 192.168.99.1:51576 conn6: { driver: { name: "mongo-java-driver|legacy", version: "3.11.2" }, os: { type: "Windows", name: "Windows 10", architecture: "amd64", version: "10.0" }, platform: "Java/Oracle Corporation/11.0.6+8-LTS" }
  mongo_1          | 2020-03-18T21:50:58.325+0000 I  NETWORK  [listener] connection accepted from 192.168.99.1:51593 #7 (4 connections now open)
  mongo_1          | 2020-03-18T21:50:58.355+0000 I  NETWORK  [conn7] received client metadata from 192.168.99.1:51593 conn7: { driver: { name: "mongo-java-driver|async|mongo-java-driver-reactivestreams", version: "3.11.2|1.12.0" }, os: { type: "Windows", name: "Windows 10", architecture: "amd64", version: "10.0" }, platform: "Java/Oracle Corporation/11.0.6+8-LTS" }
  mongo_1          | 2020-03-18T22:04:09.075+0000 I  NETWORK  [conn6] end connection 192.168.99.1:51576 (3 connections now open)
  Gracefully stopping... (press Ctrl+C again to force)
  Stopping express_mongo-express_1 ...
  Stopping express_mongo_1         ...
  Killing express_mongo_1          ... done                                                                                              PS C:\Dockers\mongodb\express&gt; docker-compose down --remove-orphans
  Removing express_mongo-express_1 ... done                                                                                              Removing express_mongo_1         ... done                                                                                              Removing network express_mongox-compose-network
  PS C:\Dockers\mongodb\express&gt; docker-compose up
  Creating network "express_mongo-compose-network" with driver "bridge"
  Creating express_mongo-db_1 ... done                                                                                                   Creating express_mongo-express_1 ... done                                                                                              Attaching to express_mongo-db_1, express_mongo-express_1
  mongo-db_1       | 2020-03-18T22:06:12.909+0000 I  CONTROL  [main] Automatically disabling TLS 1.0, to force-enable TLS 1.0 specify --sslDisabledProtocols 'none'
  mongo-db_1       | 2020-03-18T22:06:12.913+0000 I  CONTROL  [initandlisten] MongoDB starting : pid=1 port=27017 dbpath=/data/db 64-bit host=d59ff752b4e0
  mongo-db_1       | 2020-03-18T22:06:12.913+0000 I  CONTROL  [initandlisten] db version v4.2.3
  mongo-db_1       | 2020-03-18T22:06:12.913+0000 I  CONTROL  [initandlisten] git version: 6874650b362138df74be53d366bbefc321ea32d4
  mongo-db_1       | 2020-03-18T22:06:12.913+0000 I  CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.1.1  11 Sep 2018
  mongo-db_1       | 2020-03-18T22:06:12.913+0000 I  CONTROL  [initandlisten] allocator: tcmalloc
  mongo-db_1       | 2020-03-18T22:06:12.914+0000 I  CONTROL  [initandlisten] modules: none
  mongo-db_1       | 2020-03-18T22:06:12.914+0000 I  CONTROL  [initandlisten] build environment:
  mongo-db_1       | 2020-03-18T22:06:12.914+0000 I  CONTROL  [initandlisten]     distmod: ubuntu1804
  mongo-db_1       | 2020-03-18T22:06:12.917+0000 I  CONTROL  [initandlisten]     distarch: x86_64
  mongo-db_1       | 2020-03-18T22:06:12.917+0000 I  CONTROL  [initandlisten]     target_arch: x86_64
  mongo-db_1       | 2020-03-18T22:06:12.917+0000 I  CONTROL  [initandlisten] options: { net: { bindIp: "*" }, security: { authorization: "enabled" } }
  mongo-db_1       | 2020-03-18T22:06:12.917+0000 W  STORAGE  [initandlisten] Detected unclean shutdown - /data/db/mongod.lock is not empty.
  mongo-db_1       | 2020-03-18T22:06:12.918+0000 I  STORAGE  [initandlisten] Detected data files in /data/db created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
  mongo-db_1       | 2020-03-18T22:06:12.918+0000 W  STORAGE  [initandlisten] Recovering data from the last clean checkpoint.
  mongo-db_1       | 2020-03-18T22:06:12.918+0000 I  STORAGE  [initandlisten]
  mongo-db_1       | 2020-03-18T22:06:12.918+0000 I  STORAGE  [initandlisten] ** WARNING: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine
  mongo-db_1       | 2020-03-18T22:06:12.918+0000 I  STORAGE  [initandlisten] **          See http://dochub.mongodb.org/core/prodnotes-filesystem
  mongo-express_1  | Waiting for mongo:27017...
  mongo-express_1  | /docker-entrypoint.sh: line 14: mongo: Name does not resolve
  mongo-db_1       | 2020-03-18T22:06:12.919+0000 I  STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=486M,cache_overflow=(file_max=0M),session_max=33000,eviction=(threads_min=4,threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000,close_scan_interval=10,close_handle_minimum=250),statistics_log=(wait=0),verbose=[recovery_progress,checkpoint_progress],
  mongo-db_1       | 2020-03-18T22:06:13.820+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569173:820960][1:0x7fc8832f2b00], txn-recover: Recovering log 6 through 7
  mongo-db_1       | 2020-03-18T22:06:13.852+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569173:852058][1:0x7fc8832f2b00], txn-recover: Recovering log 7 through 7
  mongo-db_1       | 2020-03-18T22:06:13.905+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569173:905743][1:0x7fc8832f2b00], txn-recover: Main recovery loop: starting at 6/5760 to 7/256
  mongo-db_1       | 2020-03-18T22:06:13.987+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569173:987253][1:0x7fc8832f2b00], txn-recover: Recovering log 6 through 7
  mongo-db_1       | 2020-03-18T22:06:14.031+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569174:31988][1:0x7fc8832f2b00], txn-recover: Recovering log 7 through 7
  mongo-db_1       | 2020-03-18T22:06:14.064+0000 I  STORAGE  [initandlisten] WiredTiger message [1584569174:64661][1:0x7fc8832f2b00], txn-recover: Set global recovery timestamp: (0, 0)
  mongo-db_1       | 2020-03-18T22:06:14.106+0000 I  RECOVERY [initandlisten] WiredTiger recoveryTimestamp. Ts: Timestamp(0, 0)
  mongo-db_1       | 2020-03-18T22:06:14.115+0000 I  STORAGE  [initandlisten] Timestamp monitor starting
  mongo-db_1       | 2020-03-18T22:06:14.122+0000 I  SHARDING [initandlisten] Marking collection local.system.replset as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.126+0000 I  STORAGE  [initandlisten] Flow Control is enabled on this deployment.
  mongo-db_1       | 2020-03-18T22:06:14.126+0000 I  SHARDING [initandlisten] Marking collection admin.system.roles as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.126+0000 I  SHARDING [initandlisten] Marking collection admin.system.version as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.130+0000 I  SHARDING [initandlisten] Marking collection local.startup_log as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.130+0000 I  FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/data/db/diagnostic.data'
  mongo-db_1       | 2020-03-18T22:06:14.132+0000 I  SHARDING [LogicalSessionCacheRefresh] Marking collection config.system.sessions as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.133+0000 I  SHARDING [LogicalSessionCacheReap] Marking collection config.transactions as collection version: &lt;unsharded&gt;
  mongo-db_1       | 2020-03-18T22:06:14.133+0000 I  NETWORK  [listener] Listening on /tmp/mongodb-27017.sock
  mongo-db_1       | 2020-03-18T22:06:14.133+0000 I  NETWORK  [listener] Listening on 0.0.0.0
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Invalid argument
  mongo-express_1  | Wed Mar 18 22:06:14 UTC 2020 retrying to connect to mongo:27017 (2/5)
  mongo-express_1  | /docker-entrypoint.sh: line 14: mongo: Name does not resolve
  mongo-db_1       | 2020-03-18T22:06:14.133+0000 I  NETWORK  [listener] waiting for connections on port 27017
  mongo-db_1       | 2020-03-18T22:06:15.054+0000 I  FTDC     [ftdc] Unclean full-time diagnostic data capture shutdown detected, found interim file, some metrics may have been lost. OK
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Invalid argument
  mongo-express_1  | Wed Mar 18 22:06:15 UTC 2020 retrying to connect to mongo:27017 (3/5)
  mongo-express_1  | /docker-entrypoint.sh: line 14: mongo: Name does not resolve
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Invalid argument
  mongo-express_1  | Wed Mar 18 22:06:16 UTC 2020 retrying to connect to mongo:27017 (4/5)
  mongo-express_1  | /docker-entrypoint.sh: line 14: mongo: Name does not resolve
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Invalid argument
  mongo-express_1  | Wed Mar 18 22:06:18 UTC 2020 retrying to connect to mongo:27017 (5/5)
  mongo-express_1  | /docker-entrypoint.sh: line 14: mongo: Name does not resolve
  mongo-express_1  | /docker-entrypoint.sh: line 14: /dev/tcp/mongo/27017: Invalid argument
  mongo-express_1  | Welcome to mongo-express
  mongo-express_1  | ------------------------
  mongo-express_1  |
  mongo-express_1  |
  mongo-express_1  | Mongo Express server listening at http://0.0.0.0:8081
  mongo-express_1  | Server is open to allow connections from anyone (0.0.0.0)
  mongo-express_1  |
  mongo-express_1  | /node_modules/mongodb/lib/server.js:265
  mongo-express_1  |         process.nextTick(function() { throw err; })
  mongo-express_1  |                                       ^
  mongo-express_1  | Error [MongoError]: failed to connect to server [mongo:27017] on first connect
  mongo-express_1  |     at Pool.&lt;anonymous&gt; (/node_modules/mongodb-core/lib/topologies/server.js:326:35)
  mongo-express_1  |     at Pool.emit (events.js:311:20)
  mongo-express_1  |     at Connection.&lt;anonymous&gt; (/node_modules/mongodb-core/lib/connection/pool.js:270:12)
  mongo-express_1  |     at Object.onceWrapper (events.js:418:26)
  mongo-express_1  |     at Connection.emit (events.js:311:20)
  mongo-express_1  |     at Socket.&lt;anonymous&gt; (/node_modules/mongodb-core/lib/connection/connection.js:175:49)
  mongo-express_1  |     at Object.onceWrapper (events.js:418:26)
  mongo-express_1  |     at Socket.emit (events.js:311:20)
  mongo-express_1  |     at emitErrorNT (internal/streams/destroy.js:92:8)
  mongo-express_1  |     at emitErrorAndCloseNT (internal/streams/destroy.js:60:3) {
  mongo-express_1  |   name: 'MongoError',
  mongo-express_1  |   message: 'failed to connect to server [mongo:27017] on first connect'
  mongo-express_1  | }
  express_mongo-express_1 exited with code 1
  </code></pre>