Configure ThinManager for GRE Tunnel

Configure ThinManager for GRE Tunnel

Symptom:
When configuring ThinManager to work through multiple firewalls and a GRE tunnel you need to modify some ThinManager server settings. 

Knowing the firewall maximum tftp packet size is important. In our case Fortinet was 1200 MTU. 

Resolution:
  1. Open ThinManager
  2. Select the ThinManager server tab
  3. Right click the ThinManager server to open the configuration wizard
  4. Click next 8 times to navigate to the TFTP settings page
    1. Set the Maximum packet size
    2. Check 'enable firewall compatible TFTP'
    3. Check 'set don't fragment flag'
  5. Finish and save these settings. 



Reboot the thinclient to request a new connection. The connection should be successful and much faster.