CMM3 upgrade issue from 2.2 to 3.1. The KB is reported only for upgrading from 2.2 to 3.1 version

If you are unable to upgrade the CMM3 from 2.2 to 3.1 version and getting a CNUT error message "Cannot Connect to device" please follow the below steps.

  • Make sure that the CMM3 has reachability to your Laptop irrespective of CMM3 is on the same subnet or different subnet.


  • Confirm the SNMP configurations on both CMM3 and CNUT Server are same. On CMM3 this is under Configuration >> SNMP >> Read Permissions set to ‘’Read/Write’’ and the set the same community string (default is Canopy).


  • On CMM3, Verify the root password or enter your own password under "Full Access Password" tab for the hidden user account "root" (This option is available only for CMM3 running software version below 3.0)


  • Save and rebooted the CMM3.


  • In the CNUT application, set the “root” password same as what was set on CMM3 under "Full Access Password" tab and select the SNMP version as V1/V2c (by default V2c is selected on the radio)

Root password can be changed under :-  Edit >> Preferences >> Under Account >>Device password