L2TP VPN - Remote Printing Slow or Doesn't Print Until Disconnection

Strange issue when attempting to remote print when connected to an L2TP VPN

Scenario:

  • XG 115 v18 (latest) at user's office
  • At an offsite location user has a Brother DCP-7065DN printer on wired Eithernet
  • User at offsite location with MBP (Mojave) has printer configured and can print in normal fashion
  • User connect to XG 115 at office via L2TP VPN
  • User connects via RDP to Windows workstation
  • Viewing printers on remote Win workstation shows the redirected printers (that are set up on Mac)
  • From Win workstation, user initiates print job to printer mentioned above
  • Mac printer status first shows: "Printing - Connecting to Printer", then later "Printing - The printer is not responding"
  • Print job never prints UNTIL user disconnects VPN connection.
  • Print job prints almost immediately

Using same scenarios as above but...

  • User connects Mac workstation to same printer via USB (creates a separate print device from the Ethernet connected device).
  • Initiates a VPN connection
  • Starts RDP, connects to remote Win workstation
  • Initiate print job to USB connected printer
  • Print job prints almost immediated (while still connected to VPN)...as expected.

What to look for? How to diagnose this issue?

Note: In attempt to determine issue, on the Win workstation, we were going to try to define the printer at the remote location as a remote networked IP printer) When connected to VPN, from the Win workstation cannot ping the address of the printer at offsite location.



Edited TAGs
[edited by: emmosophos at 4:35 PM (GMT -8) on 17 Jan 2022]
  • Can the Mac user print to the printer directly while VPN or RDP (not totally clear to me) is running? I'm thinking of how a VPN connection can force all traffic down the VPN tunnel, if configured that way, which would cut the Mac off from its printer. RDP or your VPN might do the same.

    Also, what are the IP address ranges on the Mac's local ethernet and at the Windows workstation's local network? It's possible that they have the same network which would confuse routing. (The old problem where a home user uses 192.168.1.0/24 and their small office also happens to use 192.168.1.0/24 and they have problems when they VPN to the office.)

  • Hi Wayne,

    Just to be clear the user can only RDP after a VPN connection is established.
    I believe the answer is yes to whether the user can print to the printer when the VPN is connected, but TBH I am not totally sure. I would have to check the split tunnel configuration.

    And yes, it is two totally different subnets 192.168.1.0/24 on the remote, 10.5.5.0/24 on the office network.

    It's one of situations where it now works correctly with the USB connection, the user is an accountant / cpa...tax season...so at this point it is a non-issue as it works with USB. So might not get opportunity to test further till maybe months down the road.

    Also, in reflection of what I stated before about the Win machine not being able to ping the printer on the remote network. Having confusion in my head on whether that should be possible or not.

    Thanks for the feed for thought feedback :-)

    Lonnie

  • I hear you... if USB works, that's good enough. I connect our printer to an ancient Apple Time Capsule (via USB) because the printer is also ancient and unsupported and the software is too out of date to run on modern Macs, but I can make it work by copying a couple of configuration files -- carefully preserved over the years -- to each new Mac. The printer has an ethernet port, but I couldn't get any Macs to talk directly to it. It's an ancient Canon inkjet but Canon still sells the ink at a reasonable (for Canon) price, and the printer simply never jams or has dried ink.

  • Yea, as tech people we have this burning desire to resolve the issue for the intended way it is 'supposed' to work. But sometimes you just have to accept an alternate method.

    :-)

    Lonnie