I've been looking into this, as I got quite some error messages.
One of it lead me to a clue:
Did not receive expected prompt after terminal length 0 command
According to the Mellanox help, the Terminal length only allows an int between 5 and 999 for the length - so I set mine to 999
Private Const COMMAND_DISABLEPAGING = "terminal length 999"
As long as the config is less that 999 lines, the issue has been resolved for now
So now it's up to next issue, hopefully I'll get there once, where all goes ok.