For us, a normal temp is between 99 to 101. degrees...........A lot also depends on the circumstances of how or when the temp is taken.
I personally wouldn't panic over white snots and the 101.7 degree temp by itself. I would also take into account the horse's appetite and if they were alert or depressed....... If the horse was off their feed and acting "off" or depressed in any way, I would be watching them......taking their temperature again, making sure the manure was normal, etc..... and then let my vet know. I would also watch their respiration and heart rate.