Command Line Reference Guide
pause-
threshold
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.
resume-offset 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,
refer to 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 Description
9.2(1.0) Introduced on the Z9500.
8.3.19.0 Introduced on the S4820T.
8.3.11.1 Introduced on the Z9000.
8.3.7.0 Introduced on the S4810.
8.1.1.0 Introduced on the E-Series ExaScale.
6.5.1.9/7.4.1.0 Introduced on the E-Series.
7.8.1.0 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
flow control frame sent by the switch. The discard threshold should be larger than
the buffer threshold so that the buffer holds at least hold at least three packets.
Changes in the flow-control values may not be reflected automatically in the show
interface
output. As a workaround, apply the new settings, execute shut then
708
Interfaces