Connect to a Headless PRO Client

CrashPlan was built with the assumption that the desktop process and the service/backup engine would be running on the same machine. However, this is an unsupported workaround that we provide for those that wish to manage a “headless” service/backup engine on another machine.

CrashPlan PRO Client has two components

1. PRO Client service: This always running from the moment you install CrashPlan and continues to run even if you log out. It is responsible for the actual backup functions.
   • Also referred to as the CrashPlan Engine
2. PRO Client UI: This runs as a desktop application that you can launch from a user's desktop. This is what most people refer to when they say PRO Client.

This article describes connecting a PRO Client UI to a PRO Client service running on a remote computer. This is a great way to remotely administer a PRO Client that is running as a backup destination on a machine.

It's also a way to administer PRO Client on a machine with a non-graphical environment (headless mode), like a Linux or Solaris server.

• Have a good understanding of networking, TCP/IP
• Feel comfortable using a command line terminal
• Be familiar with SSH

A common question that people ask is:

“How do I put CrashPlan PRO Client into Headless Mode?”

Answer- You do not have to do anything to run in 'headless mode'. Headless just means you do not run PRO Client UI. The PRO Client service is running once you install CrashPlan PRO Client.

When you launch PRO Client UI, it connects to PRO Client Service on port 4282 which is bound to the loopback device 127.0.0.1, or localhost.

This is the key point to being able to connect to the service remotely. Because the port is bound to the loopback device, you cannot connect to it directly via a public network interface.

To connect to PRO Service remotely, we use SSH to forward local traffic to the service on the remote machine.

1. Install & start engine on host 1.2.3.4
   This is the far away text-only server.
2. Install CrashPlan on your local desktop.
   Use Mac, Windows, Linux. It doesn't matter which platform you use.
3. Open the CrashPlan folder of your local install.
4. Open the conf folder.
   1. Shut down the Desktop UI if it's running.
   2. In the file called ui.properties change the service port to 4200.
      

      servicePort=4200

5. Forward port 4200 locally to port 4243 on our remote server using SSH: in terminal type:
   

   ssh -L 4200:localhost:4243 yourusername@1.2.3.4

6. Run your CrashPlan UI.
   You're now connected to remote CrashPlanEngine and you can configure it however you wish.

1. In the ui.properties file, comment out (#) the servicePort change.
2. Be sure to save the change.
   

   #servicePort=4200

That's it! The next time you use the UI it will connect to your local CrashPlan again.

Putty is a free Windows SSH client that you can use to do the port-forwarding necessary to control a remote CrashPlan client.

• Be sure CrashPlan is running on your remote machine.
• Verify (with netstat) that it is listening on port 4242 on all addresses and on port 4243 on the local address (This is the UI service port).

netstat -na | grep LISTEN | grep 42

We want to use SSH to tunnel a local Windows port (4200) to the remote host's service port (4243).

1. Enter the IP for SSH as you normally would, but don't open the connection yet.
   
   
2. In the Connection > SSH > Tunnels section, add the following:
   
   
3. Now open the session.
4. You can use telnet to confirm the connection:

telnet localhost 4200

Once you have confirmed the connection you should be able to stop the local CrashPlan Desktop application, make sure the servicePort is 4200 in the conf/ui.properties file and restart the Desktop UI.

CrashPlan normally tries to use more CPU when it detects that a user is “away” or idle. Headless clients are almost always in this state, so will try to use a larger percentage of available CPU. If you observe high load when running a hosted client consider lowering the allowed CPU percentage in the CrashPlan PRO Client.