Configuring Interface Speed And Duplex Mode; Speed And Duplex Configuration Guidelines - Cisco 3845 - Security Bundle Router Software Manual

Configuring Ethernet Interfaces
Table 9-2 Default Ethernet Configuration
Feature
Operating mode
Allowed VLAN range
Default VLAN (for access ports)
Native VLAN (for IEEE 802.1Q trunks)
VLAN trunking
Port enable state
Port description
Speed
Duplex mode
IEEE 802.3x flow control
EtherChannel
Broadcast, multicast, and unicast storm control
Port Fast
Auto-MDIX
Cisco Discovery Protocol (CDP)

Configuring Interface Speed and Duplex Mode

Ethernet interfaces on the switch operate at 10, 100, or 1000 Mb/s or and in either full- or half-duplex
mode. In full-duplex mode, two stations can send and receive traffic at the same time. Normally, 10-Mb/s
ports operate in half-duplex mode, which means that stations can either receive or send traffic.
Switch models include combinations Gigabit Ethernet (10/100/1000-Mb/s) ports and small form-factor
pluggable (SFP) module slots supporting SFP modules.
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Speed and Duplex Configuration Guidelines

When configuring an interface speed and duplex mode, note these guidelines:
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Cisco ME 3800X and 3600X Switch Software Configuration Guide
9-14
Speed and Duplex Configuration Guidelines, page 9-14
Setting the Interface Speed and Duplex Parameters, page 9-15
You can configure interface speed on Gigabit Ethernet (10/100/1000-Mb/s) ports. You can configure
Gigabit Ethernet ports to full-duplex mode or to autonegotiate. You also can configure Gigabit
Ethernet ports to half-duplex mode if the speed is 10 or 100 Mb/s. Half-duplex mode is not
supported on Gigabit Ethernet ports operating at 1000 Mb/s.
You cannot configure speed on SFP module ports or on 10 Gigabit Ethernet ports, but you can
configure speed to not negotiate (nonegotiate) if connected to a device that does not support
autonegotiation.
Default Setting
Layer 2 or switching mode (switchport command).
VLANs 1– 4094.
VLAN 1 (Layer 2 interfaces only).
VLAN 1 (Layer 2 interfaces only).
Switchport mode access (Layer 2 interfaces only).
Enabled.
None defined.
Autonegotiate.
Autonegotiate.
Flow control is set to receive: off. It is always off for sent packets.
Disabled on all Ethernet ports. See
EtherChannels."
Disabled. See the "Default Storm Control Configuration" section on
page 19-3.
Disabled. See the "Default Optional Spanning-Tree Configuration"
section on page 15-5.
Enabled.
Enabled.
Chapter 9 Configuring Interfaces
Chapter 28, "Configuring
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