The problem has occurred when it had restarted several times a machine connected to a port in one of a switches and suddenly has stopped answering PING this machine(although is up, recognizes MAC, etc). The same has already happened in a couple of occasions and has been solved by restarting the switch, but now we can not do it. Make a shutdown / no shutdown of the port does not solve the problem.
The switch is a WS-C3560-48TS and the version you have installed a 12.2 (35) SE5.
Anybody knows that it can be happening?