We are using 6500s a backbone and 3560s and 2960 as end user switches. We have PDUs and air conditioner for system room and they have Ethernet connections to 2960s. Yesterday power of air conditioners are gone for one second. Then Their web interfaces started not to work.We can ping air conditioners but web interfaces are not working. Then we reset the 2960s, air conditioner web interfaces are working now. What should the problem be? I know that if you can ping the device, everything else should work.