CLI Reference Guide-R05

Chapter 11 | Interface Commands
Interface Configuration
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discard This command discards CDP or PVST packets. Use the no form to forward the
specified packet type to other ports configured the same way.
Syntax
[no] discard {cdp | pvst}
cdp – Cisco Discovery Protocol
pvst – Per-VLAN Spanning Tree
Default Setting
Default - Forward CDP and PVST packets
Command Mode
Interface Configuration (Ethernet)
Command Usage
Use the no discard command to allow CDP or PVST packets to be forwarded to
other ports in the same VLAN which are also configured to forward the specified
packet type.
Example
The following example forwards CDP packets entering port 5.
Console(config)#interface ethernet 1/5
Console(config-if)#no discard cdp
Console(config-if)#
flowcontrol This command enables flow control. Use the no form to disable flow control.
Syntax
[no] flowcontrol
Default Setting
Disabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
◆ 1000BASE-T does not support forced mode. Auto-negotiation should always be
used to establish a connection over any 1000BASE-T port or trunk.
◆ Flow control can eliminate frame loss by “blocking” traffic from end stations or
segments connected directly to the switch when its buffers fill. When enabled,
back pressure is used for half-duplex operation and IEEE 802.3-2002 (formally
IEEE 802.3x) for full-duplex operation.