Layer 2 Switching Commands 382Ethernet Configuration CommandsDell EMC Networking N1100-ON/N1500/N2000/N2100-ON/N3000/N3100-ON/N4000 Series SwitchesDell EMC Networking switches support a variety of configuration options tooptimize network operations. Features such as flow-control and jumbo framesare supported along with a variety of commands to display traffic statistics aswell as limit the effects of network loops or other network issues.Jumbo frame technology is employed in certain situations to reduce the taskload on a server CPU and to transmit large amounts of data efficiently. Jumboframes technology predominantly appears where certain applications wouldbenefit from using a larger frame size, e.g. Network File System (NFS). Thelarger frame size eliminates some of the need for fragmentation, leading togreater throughput. The increase in throughput is particularly valuable ondata center servers where the larger frame size increases efficiency of thesystem and allows processing of more requests. The Dell EMC Networkingjumbo frames feature extends the standard Ethernet MTU (Max Frame Size)from 1518 (1522 with VLAN header) bytes to 9216 bytes. However, any deviceconnecting to the same broadcast domain should support the same or largerMTU.Flow control is a mechanism or protocol used to temporarily suspendtransmission of data to a device to avoid overloading the device receive path.Dell EMC Networking switching implements the flow control mechanismdefined in IEEE 802.3 Annexes 31A and 31B (formerly IEEE 802.3x). DellEMC Networking switches implement receive flow control only. They neverissue a flow control PAUSE frame when congested, but do respect flowcontrol PAUSE frames received from other switches. Disabling flow controlcauses the switch to ignore received PAUSE frames. Flow control is enabledby default for all ports.Storm control allows for rate limiting of specific types of packets through theforwarding plane. The administrator can configure the absolute rate inpackets-per-second for the Storm control threshold. Each classified packettype (broadcast, multicast, or unicast) can be enabled/disabled per port, andthe threshold level at which Storm-Control is active is also configurable per-port and per-type (as a percentage of interface speed).
