Just a little heads up, be careful when running nessus against networked point of sale terminals (POS). I was doing an assessment at a large hotel and the scan seemed to take their front desk systems. I was running in "polite" mode with safe checks enabled and they were windows-based terminals so i couldnt figure out why nessus would crash them but when i excluded them from the scan, they seemed to be OK. Perhaps they are just sensitive to alot of network traffic or maybe their hospitality app crashes easily. I couldnt absolutely verify that nessus was causing the problem but rather than spend alot of time trying to trouble shoot it and leave their front desk down, i backed off and as a result didnt end up scanning those machines. As it turns out, theres no real good time to go back and do it, as they are up and manned 24/7 though coming back at 3am might work, but the client didnt want to pay for the added expense.
Either way, i though i would give a heads up out there to anyone running scans in these kinds of environments and see if anyone else has had similar experiences.
