Hi Alemabrahao,   Thanks for more info, however, i has been check each access switch have the rstp root via core switch with priority 4096 which is correct path. not sure why still getting stp high rate, or i have to adjust priority to 0? even those root switch is already core switch. I also review the physical cable that might be suspected connection loop and I'm sure now that our network is loop free but still getting those alerts and sometimes no alert.     ... View more