I am facing an issue in LAN. I have got 2 core switches and 52 access switches. We i doa continous ping i am getting request time out, and at that time i cannot access the switch. So the users connected to that switches are affected. Its only happening on 10 switches only. (only on 2950). But there are 2950 switches which are working perfectly. My core switch is vey old model (3500). Kindly advice is it a problem due to core switch or the access switches.