While executing my suite dynamically on grid using docker-compose, I am getting the following exception stacktrace:

```
org.openqa.selenium.remote.UnreachableBrowserException: Could not start a new session. Possible causes are invalid address of the remote server or browser start-up failure.
03:52:47 Build info: version: 'unknown', revision: 'unknown', time: 'unknown'
03:52:47 System info: host: 'ip-10-33-0-63', ip: '10.33.0.63', os.name: 'Linux', os.arch: 'amd64', os.version: '4.4.0-1069-aws', java.version: '1.8.0_151'
03:52:47 Driver info: driver.version: RemoteWebDriver
03:52:47    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:573)
03:52:47    at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:213)
03:52:47    at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:131)
03:52:47    at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:144)
03:52:47    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
03:52:47    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
03:52:47    at java.lang.reflect.Method.invoke(Method.java:498)
03:52:47    at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:131)
03:52:47    at org.testng.internal.MethodInvocationHelper.invokeMethodConsideringTimeout(MethodInvocationHelper.java:61)
03:52:47    at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:511)
03:52:47    at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:241)
03:52:47    at org.testng.internal.Invoker.invokeMethod(Invoker.java:581)
03:52:47    at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:792)
03:52:47    at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1103)
03:52:47    at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:140)
03:52:47    at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:122)
03:52:47    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
03:52:47    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
03:52:47    at java.lang.Thread.run(Thread.java:748)
03:52:47 Caused by: java.net.ConnectException: Failed to connect to /10.33.0.220:4444
03:52:47    at okhttp3.internal.connection.RealConnection.connectSocket(RealConnection.java:247)
03:52:47    at okhttp3.internal.connection.RealConnection.connect(RealConnection.java:165)
03:52:47    at okhttp3.internal.connection.StreamAllocation.findConnection(StreamAllocation.java:257)
03:52:47    at okhttp3.internal.connection.StreamAllocation.findHealthyConnection(StreamAllocation.java:135)
03:52:47    at okhttp3.internal.connection.StreamAllocation.newStream(StreamAllocation.java:114)
03:52:47    at okhttp3.internal.connection.ConnectInterceptor.intercept(ConnectInterceptor.java:42)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
03:52:47    at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.java:93)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
03:52:47    at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.java:93)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
03:52:47    at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.java:126)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
03:52:47    at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
03:52:47    at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:200)
03:52:47    at okhttp3.RealCall.execute(RealCall.java:77)
03:52:47    at org.openqa.selenium.remote.internal.OkHttpClient.execute(OkHttpClient.java:103)
03:52:47    at org.openqa.selenium.remote.ProtocolHandshake.createSession(ProtocolHandshake.java:105)
03:52:47    at org.openqa.selenium.remote.ProtocolHandshake.createSession(ProtocolHandshake.java:74)
03:52:47    at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:136)
03:52:47    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:552)
03:52:47 Caused by: java.net.ConnectException: Connection refused (Connection refused)
03:52:47    at java.net.PlainSocketImpl.socketConnect(Native Method)
03:52:47    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
03:52:47    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
03:52:47    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
03:52:47    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
03:52:47    at java.net.Socket.connect(Socket.java:589)
03:52:47    at okhttp3.internal.platform.Platform.connectSocket(Platform.java:129)
03:52:47    at okhttp3.internal.connection.RealConnection.connectSocket(RealConnection.java:245)

```

This is occurring while executing: 

```
return (new RemoteWebDriver(new URL(url), new FirefoxOptions()));

```

This is also happening for chrome. I recently upgraded the selenium to the latest version, i.e 3.141.59.

The `docker-compose.yml` is: 

```
version: "3"
services:
  selenium-hub:
    image: selenium/hub:3.141.59-bismuth
    container_name: selenium-hub
    ports:
      - "4444:4444"
    environment:
      - GRID_BROWSER_TIMEOUT=30

  chrome:
    image: selenium/node-chrome:3.141.59-bismuth
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub
      - HUB_PORT=4444

  firefox:
    image: selenium/node-firefox:3.141.59-bismuth
    depends_on:
      - selenium-hub
    environment:
      - HUB_HOST=selenium-hub
      - HUB_PORT=4444
    volumes:
      - "/dev/shm:/dev/shm"

```

This is happening both in Jenkins as well as when I execute it in my system from cmd. I am not sure if the issue is related to selenium or networks. If there are other links to a solution, please share here. Thanks for any help in advance. 

**UPDATE EDIT:**

Startup:

1) Build project (using maven-assembly-plugin) by **mvn clean install -DskipTests=true**

2) Start Grid: sudo docker-compose up -d --scale chrome=5 --scale firefox=3

3) Run executable jar.

4) Remove Grid: sudo docker-compose down

**Update:**

**Adding Hub Config:**

```
Config for the hub :
browserTimeout : 30
debug : false
jettyMaxThreads : -1
host : 192.168.80.2
port : 4444
role : hub
timeout : 1800
cleanUpCycle : 5000
capabilityMatcher : org.openqa.grid.internal.utils.DefaultCapabilityMatcher
newSessionWaitTimeout : -1
throwOnCapabilityNotPresent : true
registry : org.openqa.grid.internal.DefaultGridRegistry

The final configuration comes from:
the default :
browserTimeout : 0
debug : false
host : 0.0.0.0
port : 4444
role : hub
timeout : 1800
cleanUpCycle : 5000
capabilityMatcher : org.openqa.grid.internal.utils.DefaultCapabilityMatcher
newSessionWaitTimeout : -1
throwOnCapabilityNotPresent : true
registry : org.openqa.grid.internal.DefaultGridRegistry
updated with command line options:
-role hub -hubConfig /opt/selenium/config.json
and configuration loaded from /opt/selenium/config.json:
{
"host": "0.0.0.0",
"port": 4444,
"role": "hub",
"maxSession": 5,
"newSessionWaitTimeout": -1,
"capabilityMatcher": "org.openqa.grid.internal.utils.DefaultCapabilityMatcher",
"throwOnCapabilityNotPresent": true,
"jettyMaxThreads": -1,
"cleanUpCycle": 5000,
"browserTimeout": 30,
"timeout": 1800,
"debug": false
}

```

**Adding node config:**

```
browserTimeout: 30
debug: false
jettyMaxThreads: -1
host: 192.168.80.6
port: 5555
role: node
timeout: 1800
cleanUpCycle: 5000
maxSession: 1
capabilities: Capabilities {applicationName: , browserName: chrome, maxInstances: 1, platform: LINUX, platformName: LINUX, seleniumProtocol: WebDriver, server:CONFIG_UUID: d949d886-61f4-4a3a-93f9-c2a..., version: 70.0.3538.110}
downPollingLimit: 2
hub: http://selenium-hub:4444/grid/register
id: http://192.168.80.6:5555
nodePolling: 5000
nodeStatusCheckTimeout: 5000
proxy: org.openqa.grid.selenium.proxy.DefaultRemoteProxy
register: true
registerCycle: 5000
remoteHost: http://192.168.80.6:5555
unregisterIfStillDownAfter: 60000

```