Service Manual

Parameters
rx on Enter the keywords rx on to process the received ow control frames on this port. This is the
default value for the receive side.
rx o Enter the keywords rx off to ignore the received ow control frames on this port.
tx on Enter the keywords tx on to send control frames from this port to the connected device when a
higher rate of trac is received.
tx o Enter the keywords tx off so that ow control frames are not sent from this port to the
connected device when a higher rate of trac is received.
Defaults
Command Modes INTERFACE
Command History
This guide is platform-specic. 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
9.8(0.0) Introduced on the S3048-ON and S4048-ON.
9.7(0.0) Introduced on the S6000-ON.
9.0.2.0 Introduced on the S6000.
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 and 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 ow control, stations implementing the pause operation instruct the MAC to enable the reception of frames with a
destination address equal to this multicast address.
When a port receives trac at a higher rate than it can process, the frames are stored in the port buer. As a result, buer
usage increases. When the buer usage reaches the value specied in the “pause-threshold” argument, the port sends
PAUSE frame to the connected link partner to stop sending the trac. Eventually this reduces the buer usage. When the
buer usage drops by the value specied in the “resume-threshold”, the port again sends a PAUSE frame with 0 as wait-
time. This results in resume of the paused trac ow.
Important Points to Remember
• Do not enable tx pause when buer carving is enabled. For information and assistance, consult Dell Networking TAC.
• The only conguration applicable to half duplex ports is rx off tx off. The following error is returned:
Can’t configure flowcontrol when half duplex is configure, config ignored
• Half duplex cannot be congured when the ow control conguration is on (default is rx on tx on). The following
error is returned:
Can’t configure half duplex when flowcontrol is on, config ignored
NOTE: The ow control must be o (rx off tx off) before conguring the half duplex.
Interfaces
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