Should you be worrying that your house might fall down? There's an article, In Good Standing, by an engineer in the May issue of Log Homes Illustrated. It focuses on log homes because "Log homes are becoming more complex.... They are now three stories tall with multiple fireplaces, ..., heated floors, ... and party-sized hot tubs on decks..."
Footings and posts are carrying big loads! And an ounce of prevention is worth thinking about even though it's expensive. If you've seen those monster log homes in the log home magazines, you can see what a load is being carried. Hopefully, the ground's been tested; I think those logs will really twist if there's much settling. A friend who built a log home wanted a bigger back porch--and that thing is huge!--so she had to order longer beams. I have no idea what kind of foundation she has. I think it's sitting on the ground so there are no posts; and though it's big, it's not the lodge-type home with loads of windows that are so popular now. Homeowners are adding more and more to their homes while often subtracting walls! And even in a stick or masonry built home, check and see if those walls are load-bearing!