Periodic ELRP Requests
You can configure the interval between consecutive transmissions. If ELRP packets are received back, a message is printed to the system log file and/or a trap is sent to the SNMP manager indicating detection of a network loop.
You have the option to configure the switch to automatically disable the port where the looped packet arrived as well as the length of time (in seconds) that the port should remain disabled. When this hold time expires, the port is automatically enabled.
Should a loop occur on multiple ports, only the first port in the VLAN on which the PDU is received is disabled. The second port is ignored for 1 or 2 seconds and then if another PDU is received, that port is disabled until the loop is gone. This prevents shutting down all ports in the VLAN.