1.6. Network ports

Network ports and protocols

Secure communication
All Printix communication inside and outside the network is secured with encryption and the use of HTTPS (SSL/TLS). Documents are stored encrypted until they expire and get deleted. Documents do not need to leave your network.

• HTTPS on TCP port 443
  Secure browser communication between the components and Identity Providers, such as Microsoft (Azure AD), Google (G Suite) and others.

These ports must be open within the network:

• SNMP on UDP port 161
  Access and collect information from printers via SNMP. Both SNMPv1 and SNMPv3 is supported. ICMP message requests and replies must be allowed on the local network, as the ping command is used to discover printers.
• RAW print on TCP port 9100
  Transfer print data to the printers. The computer with Printix Client must be able to reach the printer on the network to allow printing. Print data can also be sent via LPR and TCP port 515. Use of other port numbers is also supported.
• TCP port 21335
  Forward print data to another computer running Printix Client. Encrypted.
• TCP port 21336
  Secure communication to Printix Redirector on a Windows Server.
• UDP port 21337
  Printix Discovery Protocol used to find computers running Printix Client. Not encrypted.
• UDP port 5353
  If mobile print is enabled, and is to be used with iOS/iPadOS devices, then Printix Client will broadcast AirPrint printers via the Bonjour networking protocol (Multicast DNS).

Printix Client requires two ports to be open on the local computer:

• TCP port 21338 and 21339
  Secure local communication. TCP port 21338 is used for communication between the two processes: PrintixClient.exe and PrintixService.exe. TCP port 21339 is used for listening by the Printix Client built-in web server for sign in and printing (Windows print spooler and CUPS).

If Active Directory authentication is enabled one of these ports must also be open within the network:

• Secure LDAPS on TCP 636
  Authentication of users via secure LDAPS.
• LDAP on TCP port 389
  Authentication of users via LDAP.

Windows Printix Client automatically configures the required ports in the local Windows Firewall. It does so by running the provided file: open_firewall.cmd

Web proxy and SSL inspection

Use of a web proxy and/or SSL inspection may for example prevent Sign in to Printix Client. You MUST add the printix.net domain and subdomains as exceptions so traffic is not blocked.

The syntax for adding exceptions varies depending on the software you use. Please refer to you security software documentation to determine the syntax for specifying a domain and subdomains. These are some common examples of wildcard syntax:

• *.printix.net
• .printix.net

The specific URLs that must be unblocked:

Required

• https://assets.printix.net
• https://api.printix.net
• https://auth.printix.net
• https://sign-in.printix.net
• https://drivers.printix.net
• https://software.printix.net
• wss://websocket.proxyendpoint.printix.net

Required, if you enable mobile print (Apple AirPrint)

• https://airprint.printix.net

Required for optional data extraction

• https://*.blob.core.windows.net

How does Printix Client find the web proxy?

Printix Client consists of two components:

• The user interface of Printix Client (PrintixClient.exe) which runs under the signed in user’s account
• The Printix Service (PrintixService.exe) which runs under the local system account, and handles the printing.

Printix Client use a Windows function WinHttpGetProxyForUrl (implements WPAD) to get the proxy settings from the PAC file. It also looks at the proxy settings configured for the user. If it finds a suitable set of proxy settings for the user, it remembers them in the registry under the LSA user (HKEY_USERS\S-1-5-18\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections).

Troubleshooting

• I have a web proxy and sign in to Printix Client does not work
• I have a web proxy and my printer will not install
• I do not recognize the used web proxy
• I have disabled the web proxy, but the computer still does not act as proxy

I have a web proxy and sign in to Printix Client does not work

• Sign in with Microsoft, Google or email in Printix Client just returns to Sign in.
  RESOLUTION: You MUST add the required domains (see above) as exceptions so traffic is not blocked. See also: Sign in issues.

I have a web proxy and my printer will not install

• Print drivers can not be downloaded from the Printix driver store.
  RESOLUTION: Unblock the URL https://drivers.printix.net

I do not recognize the used web proxy

• In this case the PrintixService.log file will contain the text like this: running with proxy1: https://172.23.100.13:8080/ and Unable to connect to the remote server.
  RESOLUTION: Check if the web proxy is part of the PAC file and if it should be updated/deleted.

I have disabled the web proxy, but the computer still does not act as proxy

• In this case, the PrintixService.log file may contain errors like: Proxy: Error event, Exception: proxy error
  RESOLUTION: Follow the steps below to delete settings from Windows registry.

1. Select Windows logo key + R to open Run.
2. Type: regedit, and select OK.
3. In Registry Editor browse to:
   HKEY_USERS\S-1-5-18\Software\Microsoft\
   Windows\CurrentVersion\Internet Settings\Connections

4. Delete the two entries called DefaultConnectionSettings and SavedLegacySettings.
5. Restart the computer.
6. Sign in to Printix Client again.