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5-2
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
78-15908-01
Chapter 5 Configuring Gigabit Ethernet Switching
Understanding How Gigabit Ethernet Works
Using Flow-Control Keywords
Table 5-2
describes the guidelines for using different configurations of the send and receive keywords
with the set port flowcontrol command.
Table 5-1
Send Capability by Switch Type, Module, and Ports
Switch Type
Module
Ports
Send
Catalyst 4000
Catalyst 4500
All modules except WS-X4418-GB
and WS-X4412-2GB-T
All ports except for the
oversubscribed ports listed below
No
Catalyst 4000
Catalyst 4500
WS-X4418-GB
Uplink ports (1–2)
No
Catalyst 4000
Catalyst 4500
WS-X4418-GB
Oversubscribed ports (3–18)
Yes
Catalyst 4000
Catalyst 4500
WS-X4412-2GB-T
Uplink ports (13–14)
No
Catalyst 4000
Catalyst 4500
WS-X4412-2GB-T
Oversubscribed ports (1–12)
Yes
Catalyst 4000
Catalyst 4500
WS-X4424-GB-RJ45
All ports
Yes
Catalyst 4000
Catalyst 4500
WS-X4448-GB-RJ45
WS-X4548-GB-RJ45
All ports
Yes
Catalyst 4000
Catalyst 4500
WS-X4448-GB-LX
All ports
Yes
Catalyst 2948G
All ports
All ports
No
Catalyst
2948G-GE-TX
Ports 1–48
Ports 49–52
Yes
No
Catalyst 2980G
All modules
All ports
No
Table 5-2
Send and Receive Keyword Configurations
Configuration
Description
send on
Enables a local port to send pause frames to a remote port. Enter send on when a
remote port is set to receive on or receive desired.
send off
Prevents a local port from sending pause frames to a remote port. Enter send off
when a remote port is set to receive off or receive desired.
send desired
Indicates preference to send pause frames, but autonegotiates flow control. You can
enter send desired when a remote port is set to receive on, receive off, or receive
desired.
receive on
Enables a local port to process pause frames that a remote port sends. Enter receive
on when a remote port is set to send on or send desired.