Dell C1048P Port Extender Networking Command-Line Reference Guide for the C900 - Page 871

tx off pause-threshold resume-offset Enter the keywords tx off so that flow control frames are not sent from this port to the connected device when a higher rate of traffic is received. Enter the keyword pause-threshold to configure the buffer threshold (in Kilobytes) at which the interface starts transmitting pause frames for link-level flow control. Valid values are 1 to 12480KB. The default is 60KB. Enter the keyword resume-offset to configure the buffer threshold (in Kilobytes) at which the interface resumes transmitting offset frames for link-level flow control. Valid values are 1 to 12480KB. The default is 9KB. Defaults An interface ignores flow-control frames received from other network devices (rx off) and does not transmit pause frames (tx off). Command Modes INTERFACE Command History This guide is platform-specific. For command information about other platforms, see the relevant Dell Networking OS Command Line Reference Guide. The following is a list of the Dell Networking OS version history for this command. Version 9.9(0.0) 9.2(1.0) 8.3.19.0 8.3.11.1 8.3.7.0 8.1.1.0 6.5.1.9/7.4.1.0 7.8.1.0 Description Introduced on the C9010. Introduced on the Z9500. Introduced on the S4820T. Introduced on the Z9000. Introduced on the S4810. Introduced on the E-Series ExaScale. Introduced on the E-Series. Introduced on the C-Series and S-Series with the thresholds option. Usage Information The globally assigned 48-bit Multicast address 01-80-C2-00-00-01 is used to send and receive pause frames. To allow full-duplex flow control, stations implementing the pause operation instruct the MAC to enable the reception of frames with a destination address equal to this multicast address. The pause: • Starts when either the packet pointer or the buffer threshold is met (whichever is met first). When the discard threshold is met, packets are dropped. • Ends when both the packet pointer and the buffer threshold fall below 50% of the threshold settings. The discard threshold defines when the interface starts dropping the packet on the interface. This may be necessary when a connected device does not honor the Interfaces 871