1-8To do… Use the command… Remarksport-group manualport-group-nameIn port-groupviewjumboframe enableinterface interface-typeinterface-numberEnable theforwarding ofjumboframes In Ethernetinterface viewjumboframe enableUse any command.By default, the deviceallows jumbo frames withthe length of 9,216 bytesto pass through all Layer 2Ethernet interfaces.Enabling Loopback Detection on an Ethernet InterfaceIf a port receives a packet that it sent out, a loop occurs. Loops may cause broadcast storms. Thepurpose of loopback detection is to detect loops on an interface.When loopback detection is enabled on an Ethernet interface, the device periodically checks whetherthe ports have any external loopback. If it detects a loopback on a port, the device will set that port tobe under loopback detection mode.z If loops are detected on an access port, the port will be blocked. Meanwhile, trap messages will besent to the terminal, and the corresponding MAC address forwarding entries will be removed.z If loops are detected on a trunk port or a hybrid port, trap messages are sent to the terminal. If theloopback detection control function is also enabled on the port, the port will be blocked, trapmessages will be sent to the terminal, and the corresponding MAC address forwarding entries willbe removed.Follow these steps to configure loopback detection:To do… Use the command… RemarksEnter system view system-view —Enable global loopbackdetection loopback-detection enable RequiredDisabled by defaultConfigure the interval for portloopback detectionloopback-detectioninterval-time timeOptional30 seconds by defaultEnter Ethernet interface view interface interface-typeinterface-number —Enable loopback detection on aport loopback-detection enable RequiredDisabled by defaultEnable loopback detectioncontrol on a trunk port or ahybrid portloopback-detection controlenableOptionalDisabled by defaultEnable loopback detection inall the VLANs to which trunk orhybrid ports belongloopback-detection per-vlanenableOptionalEnabled only in the defaultVLAN(s) with trunk port orhybrid ports
