Administrator Guide

Usage
Information
This command applies to any physical interface with speed set to 10/100.
NOTE: Starting with Dell Networking OS version 7.8.1.0, when you use a copper SFP2 module with
catalog number GP-SFP2-1T in the S25P model of the S-Series, you can manually set its speed with
the speed command. When you set the speed to 10 Mbps or 100 Mbps, you can also execute the
duplex command.
Related
Commands
negotiation auto — enables or disables auto-negotiation on an interface.
flowcontrol
Control how the system responds to and generates 802.3x pause frames on 10 Gig ports.
Syntax
flowcontrol rx {off | on} tx {off | on}
Parameters
rx on Enter the keywords rx on to process the received flow control frames on this
port. This is the default value for the receive side.
rx off Enter the keywords rx off to ignore the received flow 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 traffic is received.
tx off 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.
Defaults Z9000: rx off 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
9.7(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 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.
When a port receives traffic at a higher rate than it can process, the frames are stored in the port
buffer. As a result, buffer usage increases. When the buffer usage reaches the value specified in the
“pause-threshold” argument, the port sends PAUSE frame to the connected link partner to stop sending
the traffic. Eventually this reduces the buffer usage. When the buffer usage drops by the value specified
in the “resume-threshold”, the port again sends a PAUSE frame with 0 as wait-time. This results in
resume of the paused traffic flow.
Important Points to Remember
502 Interfaces