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This article applies to version 6.

Other available versions:

Version 5 | Version 4icon.qnmark.png

Available in:

StandardPremiumEnterprise
Small Business
Code42 Support

Test your network connection

This article applies to version 6.

Other available versions:

Version 5 | Version 4icon.qnmark.png

Available in:

StandardPremiumEnterprise
Small Business

Overview

Sometimes the Code42 app can't make a network connection even if the Internet appears to be working. This is because the Code42 app relies on specific ports to be open. This article describes how to test connectivity on the correct ports to rule out problems with firewalls, anti-virus products, or other network issues.

This article describes the following tools to check network connections:

What are ports?

Ports are specific doorways for Internet traffic to travel through. If your computer were a building, ports would be numbered doors leading outside. If a door is locked, you can't get out. The Code42 app needs to open either of two specific doors: #443 or #4287. Other applications on your computer use other doors. So if your email and the Internet work, but the Code42 app does not, you should make sure that the proper ports are unlocked.

Before you begin

To troubleshoot a connection, you need to know the address and port you are attempting to connect to. If you do not know the address for your Code42 instance, contact your Code42 administrator or our Customer Champions​ for Code42 for Enterprise support or CrashPlan for Small Business support.

Following are common addresses and ports:

  • CrashPlan for Small Business:
    • central.crashplanpro.com 443
    • central.crashplan.com 443
  • Code42 cloud
    • central.crashplan.com 443
    • clients.us.code42.com 4282
  • Code42 on-premises authority servers: Contact your Code42 administrator for the address.
Ensure port 4287 is open
To communicate with the Code42 cloud, ensure that port 4287 is open. 

PowerShell (Windows only)

PowerShell is a scripting tool for Windows. Windows PowerShell comes installed by default in every Windows version starting with Windows 7 SP1 and Windows Server 2008 R2 SP1.

  1. In the lower-left corner, click the Windows icon and type: PowerShell
  2. At the PowerShell prompt, enter the command: New-Object System.Net.Sockets.TcpClient("<address>", <port>)
    The Code42 app uses port 443 or 4287 to connect to authority servers and the Code42 cloud. If you are unsure which port to include, test all.
    Examples:
    New-Object System.Net.Sockets.TcpClient("code42.example.com", 443)
    New-Object System.Net.Sockets.TcpClient("code42.example.com", 4287)

If the connection passes, a Connected: True message displays similar to the following:

PS C:\Users\johndoe> New-Object System.Net.Sockets.TcpClient("code42.example.com", 443)

Client              : System.Net.Sockets.Socket
Available           : 0
Connected           : True
ExclusiveAddressUse : False
ReceiveBufferSize   : 65536
SendBufferSize      : 65536
ReceiveTimeout      : 0
SendTimeout         : 0
LingerState         : System.Net.Sockets.LingerOption
NoDelay             : False

If the connection fails, a failure message displays, for example:

New-Object : Exception calling ".ctor" with "2" argument(s): "A connection attempt failed because the connected party
did not properly respond after a period of time, or established connection failed because connected host has failed to
respond 192.0.2.0:443"
At line:1 char:1
+ New-Object System.Net.Sockets.TcpClient("code42.example.com", 443)
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [New-Object], MethodInvocationException
    + FullyQualifiedErrorId : ConstructorInvokedThrowException,Microsoft.PowerShell.Commands.NewObjectCommand

If the connection fails, troubleshoot the failed connection.

Netcat (Mac and Linux only)

Netcat is a networking utility for reading from and writing to network connections using TCP or UDP. It is installed by default on Mac and Linux.

Mac

  1. Select Utilities > Terminal.
  2. Enter the command: nc -vz <address> <port>
    The Code42 app uses port 443 or 4287 to connect to authority servers and the Code42 cloud. If you are unsure which port to include, test all.
    Examples:
    nc -vz code42.example.com 443
    nc -vz code42.example.com 4287

If the connection passes, a CONNECTED message displays similar to the following:

nc -vz code42.example.com 443
found 0 associations
found 1 connections:
     1: flags=82<CONNECTED,PREFERRED>
outif en4
src 192.0.0.0 port 59064
dst 192.0.2.0 port 443
rank info not available
TCP aux info available

If the connection fails, a failure message displays, for example:

nc: connectx to code42.example.com port 444 (tcp) failed: Operation timed out

If the connection fails, troubleshoot the failed connection.

Linux

  1. Open Terminal.
  2. Enter the command: nc -vz <address> <port>
    The Code42 app uses port 443 or 4287 to connect to authority servers and the Code42 cloud. If you are unsure which port to include, test all.
    Examples:
    nc -vz code42.example.com 443
    nc -vz code42.example.com 4287

If the connection passes, a success message displays similar to the following:

Connection to code42.example.com 443 port [tcp/https] succeeded!

If the connection fails, a failure message displays, for example:

connect to code42.example.com port 443 (tcp) failed: Connection timed out

If the connection fails, troubleshoot the failed connection.

Telnet

Telnet is a protocol to provide communication over the Internet or a LAN a using a virtual terminal connection. It is installed by default on Linux and older Mac operating systems, but must be installed on Windows and macOS High Sierra 10.13.

  1. Install Telnet if it is not already installed. 
  2. Open the command prompt:
    • Windows:
      1. Select Start.
      2. Choose Run or Search.
      3. Enter: cmd.exe
    • OS X: Select Utilities > Terminal.
    • Linux: Open Terminal.
  3. Enter the command: telnet <address> <port>
    The Code42 app uses port 443 or 4287  to connect to authority servers and the Code42 cloud. If you are unsure which port to include, test all.
    Examples:
    telnet code42.example.com 443
    telnet code42.example.com 4287

If Telnet successfully connects, a message displays similar to the following:

  • Linux and Mac
telnet code42.example.com 443
Trying 192.0.2.0...
Connected to code42.com.
Escape character is '^]'.
Connection closed by foreign host.
  • Windows
    The successful connection message scrolls by quickly and you are presented with a blinking cursor on a blank screen. (You can press Enter to return to the command prompt.)

If the connection fails, troubleshoot the failed connection.

Install Telnet

Install Telnet on Windows

Telnet is not installed by default on Windows; if you try to run it you will get the message "'Telnet' is not recognized as an operable program or batch file." To install Telnet:

  1. Click Start.
  2. Select Control Panel.
  3. Choose Programs and Features.
  4. Click Turn Windows features on or off.
  5. Select the Telnet Client option.
  6. Click OK.
    A dialog box appears to confirm installation. The telnet command should now be available.

Install Telnet on Macintosh

Telnet is not installed on macOS High Sierra 10.13. To install Telnet:

  1. Paste the following into the Macintosh terminal prompt to install Homebrew, an open-source software package management system:
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
  1. Run the following command in the terminal prompt to install Telnet:
brew install telnet

Troubleshoot a failed connection

If you cannot connect, you may see one of the following messages, some other message, or no response: 

  • Connection refused
  • Operation timed out
  • Unable to connect to remote host

If your test did not connect to the other computer, your issue is caused by the computers or network configuration, not by the Code42 app. Check the following common causes of this issue:

  • Either computer's router, including its network configuration or port forwarding settings
  • Other conflicting software on either computer, such as antivirus, security, or parental control software
Further isolate the issue
If the connection test passes, there probably isn't an issue with the network. However, some firewall and anti-virus applications are capable of blocking connections on a per-application basis. Make sure the Code42 app has an exception configured in your security software. If the problem continues, contact your administrator.
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