Print Server

Compatibility

• ✅ 2.2 | ✅ 2.1 | ✅ 2.0 | ✅ 1.9 | ...

Objective

• Run QZ Tray as a dedicated service, useful for machines that cannot have QZ Tray installed (such as a Terminal Services/Citrix environment and mobile/sandboxed devices such as iOS, Android, ChromeOS).
  
  Note: If you're looking for step-by-step instructions for installing QZ Tray as a Windows service, please see this tutorial instead.

Steps

The steps will be the same for each platform, however, the way you regenerate the certificate and install it on the client will vary.

1. Install QZ Tray
2. Connect to QZ Tray
3. Remove localhost Bindings
4. Copy Files to the Client
5. Install the new certificate on the client
   • Windows
   • Linux
   • macOS
   • iOS (iPad, iPhone)
   • Android
6. Import Firefox Certificates
7. Verify secure connection

Install QZ Tray

Install QZ Tray onto the server via the desktop installer. Refer to this guide if unsure how to do this.

Connect to QZ Tray

By default, the qz.websocket.connect(); functions are bound to localhost. This can be overridden.

Note:foo.bar is the hostname of the server.

• Replace all calls to qz.websocket.connect(); with qz.websocket.connect({host: "foo.bar"});

  //qz.websocket.connect();
  qz.websocket.connect({host: "192.168.1.2"});

Deprecated

1.9

• Replace all calls to deployQZ with deployQZ("foo.bar");

  //deployQZ();
  deployQZ("192.168.1.2");

That's it! At this point, an HTTP connection can be made from a client to the server running QZ Tray. The steps below illustrate how to establish an HTTPS connection.

HTTPS Support

Trusted CA Certificate

• Organizations wishing to use a 3rd-party Trusted CA SSL certificate can do so by manually shimming it into the software. If you do not have or do not wish to use a CA certificate, please see remove localhost bindings section instead.

  java -jar qz-tray.jar certgen --key "privkey.pem" --cert "fullchain.pem"
  
  # or for a pfx/pkcs#12 file
  java -jar qz-tray.jar certgen --pfx "mycert.pfx" --pass "12345"
  
  # ... or for 2.0 please see https://github.com/qzind/tray/pull/89

Remove Localhost Bindings

HTTPS: The steps provided in this section illustrate how to create a self-signed certificate for a secure (HTTPS) connection. These steps are not needed for connections made via HTTP or connections that use a 3rd-party Trusted CA Certificate file.

For secure websockets support (HTTPS), QZ Tray generates a certificate for localhost traffic at install time called root-ca.crt. In order for QZ Tray to run on a separate machine, the hostname (usually "localhost") must exist in the certificate. This is an override which is done by running a custom script.

1. Re-run the certificate generation ("foo.bar" is the hostname that QZ Tray will run on). If you require Firefox HTTPS support, Firefox needs to be installed prior to this step.

   • This will re-generate the qz-tray.properties, root-ca.crt and qz-tray.jks

   Windows

   Open a command prompt as an administrator and run the following commands:

   Windows (QZ Tray 2.2+)

   REM Regenerate the certificate
   cd "%PROGRAMFILES%\QZ Tray\"
   qz-tray-console.exe certgen --host "192.168.1.5"
   REM -- OR --
   qz-tray-console.exe certgen --hosts "domain1;domain2;..."

   Windows (QZ Tray 2.1)*

   REM Regenerate the certificate
   cd "%PROGRAMFILES%\QZ Tray\"
   java -jar qz-tray.jar certgen --host "192.168.1.5"
   REM -- OR --
   java -jar qz-tray.jar certgen --hosts "domain1;domain2;..."

   *Since 2.1.0-RC9

   Windows (QZ Tray 2.0)

   REM Regenerate the certificate
   cd "%PROGRAMFILES%\QZ Tray\"
   cscript auth\windows-keygen.js . install "foo.bar"

   

   Linux

   Linux (QZ Tray 2.2+)

   # Regenerate the certificate
   sudo /opt/qz-tray/qz-tray certgen --host "192.168.1.5"
   # -- OR --
   sudo /opt/qz-tray/qz-tray certgen --hosts "domain1;domain2;..."

   Linux (QZ Tray 2.1)*

   # Regenerate the certificate
   cd /opt/qz-tray
   sudo java -jar qz-tray.jar certgen --host "192.168.1.5"
   # -- OR --
   sudo java -jar qz-tray.jar certgen --hosts "domain1;domain2;..."

   *Since 2.1.0-RC9

   Linux (QZ Tray 2.0)

   # Reinstall completely with specified hostname
   sudo bash qz-tray-2.0.x.run -- -y "foo.bar"

   macOS

   macOS (QZ Tray 2.2+)

   # Regenerate the certificate
   sudo "/Applications/QZ Tray.app/Contents/MacOS/QZ Tray" certgen --host "192.168.1.5"
   # -- OR --
   sudo "/Applications/QZ Tray.app/Contents/MacOS/QZ Tray" certgen --hosts "domain1;domain2;..."

   macOS (QZ Tray 2.1)*

   # Regenerate the certificate
   cd "/Applications/QZ Tray.app/"
   sudo java -jar qz-tray.jar certgen --host "192.168.1.5"
   # -- OR --
   sudo java -jar qz-tray.jar certgen --hosts "domain1;domain2;..."

   *Since 2.1.0-RC9

   macOS (QZ Tray 2.0)

   # Regenerate the certificate
   sudo /Applications/QZ\ Tray.app/auth/apple-keygen.sh install "foo.bar"
   
   # Optionally, regenerate the Firefox configuration files
   sudo /Applications/QZ\ Tray.app/auth/firefox/firefox-cert.sh install "foo.bar"

2. Relaunch QZ Tray. This must be done every time you regenerate a certificate.

Note: Alternatively, you may provide an custom .properties file directly to Java using -DsslPropertiesFile=path/to/my.properties.

Copy Files to Client

1. For iOS (iPad, iPhone), skip to the iOS section below

2. Copy root-ca.crt from the server's QZ Tray shared directory to the client

   This is in Advanced, Troubleshooting, Browse Shared Folder.

3. Optional: Copy the demo folder for testing (located in QZ Tray\demo) from QZ Tray to the client.

4. Optionally, if Firefox support is needed, enable the Enterprise Roots policy

   Note: If unsure of the location of these files on your system install QZ Tray on a test system and search for them by name. They are both created by QZ Tray and can safely be overwritten.

The rest of the steps must be completed on the client

Certificate Installation

Certificate installation varies between browsers and platforms. Distributing a certificate marked for a custom hostname is a manual process which must be done on all workstations requiring HTTPS + QZ Tray.

Windows

1. Double click root-ca.crt

2. Click Install Certificate

3. Local Machine, Next

4. Choose "Trust Root Certificate Authorities" and hit Next

   

5. Click Finish. If successful, the following screen will appear:

   

Linux

1. Run the following command to install the certificate

   certutil -d sql:$HOME/.pki/nssdb -A -t TC -n  "QZ Industries, LLC" -i /path/to/root-ca.crt

macOS

1. Double click root-ca.crt

2. Choose System, Add

   

3. From KeyChain set certificate to "Always Trust"

iOS (iPad, iPhone)

1. As of 2.0.9 root-ca.crt is automatically hosted on the about status page of QZ Tray

   • To access the about page, navigate (in Safari) to the printer server on port 8182 (e.g. http://foobar:8182/)
     
     ⚠️ Warning: A bug with 2.1.0 prevents the root-ca Download from working properly on iOS and manual installation (e.g. email) is needed instead. This is fixed in 2.1.1.

   • Under the SSL section, click the "Download certificate" with the alias of the newly created certificate.

2. If you are not running QZ Tray 2.0.9 +, you will need to host the root-ca.crt somewhere so you can download it from the web (e.g. temporarily on a webpage, Google drive, etc.). The about page will not have the certificate to download.

3. Use Safari to download the root-ca.crt. Safari will automatically prompt the installation of the certificate. Chrome and other browsers will not. When Prompted, select "Allow"

   

4. The profile installer screen should automatically appear. Select "Install"

   

5. Next, go to Settings > General > About > Certificate Trust Settings. The newly installed certificate should appear. Toggle to enable full trust for root certificates

   

Android using Chrome browser (Pixel, Moto, Samsung, et cetera smart devices)

• As of the publication of this section of the tutorial (April 2, 2021), Android must have a server-side modification for the IP address of the local print-server:

qz.websocket.connect({ host: 'IPv4.ADDRESS.OF.LAN-PRINT-SERVER', usingSecure: false });

• Next, the client (tablet, smart phone) must make an exception in Chrome to allow insecure traffic from this particular address.
• Open Chrome on the smart device, and navigate to:

chrome://flags/#unsafely-treat-insecure-origin-as-secure

• From here, ENABLE the ability to use this feature, and add ws://IPv4.ADDRESS.OF.LAN-PRINT-SERVER:8182 (8182 is our first default for ws://) to the exception list

  

• You should then be able to navigate to that page from your Android Chrome browser:

  

Import Firefox certificate

Windows, MacOS

• Install the certificate to the OS per above instructions
• Navigate to about:config
• Search for security.enterprise_roots.enabled, change the value to true.

Linux

• Use the Certificates > Install directive using policies.json as described here: https://github.com/mozilla/policy-templates/blob/master/README.md#policiesjson-9

Legacy Firefox Versions

Firefox does not allow self-signed certificates to be imported directly, instead a manual import process is needed.

1. Overlay the existing Firefox files with the ones transferred over from the server.

   defaults/pref/firefox-prefs.js
   firefox-config.cfg
   

2. Again, these may be located in C:\Program Files (x86)\Mozilla Firefox\

Verify Secure Connection

1. Open sample.html in a browser

2. Right Click, Inspect Element on the sample page

3. Click the Console tab

4. Verify the secure websocket connection to 8181 succeeds. If a connection is made on a different port, reference the table below

   Secure (HTTPS)	Insecure (HTTP)
   8181	8182
   8282	8283
   8383	8384
   8484	8485

   Note: If HTTPS still fails, or you are experiencing long timeouts before a connection is made, a firewall may be blocking the connection. Try disabling the firewall, or allowing the port on the server.