Chapter1 Configuring Interfaces and Circuits
Configuring Interfaces
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Cisco Content Services Switch Routing and Bridging Configuration Guide
OL-4580-01
To remove an interface description, enter:
(config-if[2/1])# no description
Configuring Interface Duplex and Speed
By default, the CSS Fast Ethernet interface and Gigabit Ethernet interface are
configured to auto-negotiate. The CSS automatically detects the network line
speed (Fast Ethernet only) and duplex of incoming signals, and synchronizes
those parameters during data transfer. Auto-negotiation enables the CSS and the
other devices on the link to achieve the maximum common level of operation.
When using Fast Ethernet ports with older equipment that cannot transmit the
duplex and speed with the signals, you can manually configure the speed
(10 Mbps, 100 Mbps) and duplex (half or full duplex) of the CSS port to match
the transmitting equipment.
When you use Gigabit Ethernet ports, if the link does not come up (perhaps due
to traffic congestion), you may need to force the CSS and its link partner in to a
specific mode. The CSS allows you to manually select a full duplex and flow
control (pause frame) mode. Flow control allows the CSS to control traffic during
congestion by notifying the other port to stop transmitting until the congestion
clears. When the other device receives the pause frame, it temporarily stops
transmitting data packets. When the CSS detects local congestion and becomes
overwhelmed with data, the Gigabit Ethernet ports transmits a pause frame. Both
the CSS Gigabit Ethernet and its link partner must be configured with the same
pause method (asymmetric, symmetric, or both). By default, all Gigabit Ethernet
ports are configured to full duplex mode with symmetric pause (pause frames
transmitted and received by the CSS).
Note If you configure the redundancy-phy command on an interface of the master CSS
in a box-to-box redundancy configuration and then make a change to the port
settings of that interface using the phy command (for example, changing
auto-negotiate to 100Mbits-FD), the master CSS fails over to the backup CSS.
To prevent the failover from occurring, first enter the no redundancy-phy
command on the interface, change the port settings, and then reenter the
redundancy-phy command. For information about the redundancy-phy
command, refer to the Cisco Content Services Switch Redundancy Guide.
