Configuring Flow Control On Combo Ports - Alcatel-Lucent OmniSwitch 6850-48 Network Configuration Manual

Configuring Ethernet Ports

Configuring Flow Control on Combo Ports

The interfaces hybrid pause
that run in full duplex mode. Configuring flow control is done to specify whether or not an interface will
transmit, honor, or both transmit and honor PAUSE frames. PAUSE frames are used to temporarily pause
the flow of traffic between two connected devices to help prevent packet loss when traffic congestion
occurs between switches.
Using the interfaces hybrid pause command alone is sufficient to configure E2E flow control on a 24-
port OmniSwitch 6400, a 24-port OmniSwitch 6850 and an OmniSwitch 6855 running in standalone
mode. However, if a switch is a 48-port switch running in standalone mode, then a flow control VLAN is
required in addition to enabling flow control. This type of VLAN is configured using the
flow-vlan command.
Although E2E flow control is only supported on standalone OmniSwitch 6400, OmniSwitch 6850, and
OmniSwitch 6855 switches, it is possible to configure a stack of switches or a chassis-based switch to
honor PAUSE frames only. This is also done with the interfaces pause command.
Note that if autonegotiation and flow control are both enabled for an interface, then autonegotiation deter-
mines how the interface will process PAUSE frames. See
page 1-9 for more information. If autonegotiation is disabled but flow control is enabled, then the config-
ured flow control settings apply.
By default, flow control is disabled. To configure flow control for one or more ports, use the interfaces
hybrid pause command with one of the following parameters to specify how PAUSE frames are
processed:
•
tx—Transmit PAUSE frames to peer switches when traffic congestion occurs on the local interface. Do
not honor PAUSE frames from peer switches.
•
rx—Allow the interface to honor PAUSE frames from peer switches and temporarily stop sending traf-
fic to the peer. Do not transmit PAUSE frames to peer switches.
•
tx-and-rx—Transmit and honor PAUSE frames when traffic congestion occurs between peer switches.
Note. In the interfaces hybrid pause command, the copper keyword is used to configure the copper RJ-
45 10/100/1000 port while the fiber keyword is used to configure the fiber SFP connector.
For example, the following command configures port 1/23 to transmit and honor PAUSE frames:
-> interfaces 1/23 hybrid fiber pause tx-and-rx
OmniSwitch AOS Release 6 Network Configuration Guide
command is used to configure flow control (pause) settings for combo ports
September 2009
Setting Ethernet Combo Port Parameters
"Flow Control and Autonegotiation" on
interfaces e2e-
page 1-27