Cisco Catalyst 2360, Руководство по установке оборудования

Страница: 46 / 74

4-4
Catalyst 2360 Switch Hardware Installation Guide
OL-22150-02
Chapter 4 Troubleshooting
Clearing the Switch IP Address and Configuration
Switch Performance
Speed, Duplex, and Autonegotiation
If the port statistics show a large number of alignment errors, frame check sequence (FCS), or
late-collisions errors, this might mean a speed or duplex mismatch.
A common issue with speed and duplex occurs when duplex and speed settings are mismatched between
two switches, between a switch and a router, or between the switch and a workstation or server.
Mismatches can happen when manually setting the speed and duplex or from autonegotiation issues
between the two devices.
To maximize switch performance and to ensure a link, follow one of these guidelines when changing the
duplex or the speed settings.
• Let both ports autonegotiate both speed and duplex.
•
Manually set the speed and duplex parameters for the interfaces on both ends of the connection.
•
If a remote device does not autonegotiate, use the same duplex settings on the two ports. The speed
parameter adjusts itself even if the connected port does not autonegotiate.
Autonegotiation and Network Interface Cards
Problems sometimes occur between the switch and third-party network interface cards (NICs). By
default, the switch ports and interfaces autonegotiate. Laptops or other devices are commonly set to
autonegotiate, yet sometimes autonegotiation issues occur.
To troubleshoot autonegotiation problems, try manually setting both sides of the connection. If this does
not solve the problem, there could be a problem with the firmware or software on your NIC. You can
resolve this by upgrading the NIC driver to the latest version.
Cabling Distance
If the port statistics show excessive FCS, late-collision, or alignment errors, verify that the cable distance
from the switch to the connected device meets the recommended guidelines. See the
“Cables and
Adapters” section on page B-5 .
Clearing the Switch IP Address and Configuration
If you have configured a new switch with a wrong IP address, or if all of the switch LEDs start blinking
when you are trying to enter Express Setup mode, you can clear the configured IP address. The switch
returns to the factory default settings.
Note
This procedure clears the IP address and all configuration information stored on the switch. Do not
follow this procedure unless you want to completely reconfigure the switch.
1. Press and hold the Mode button ( Figure 1-1 on page 1-2 ).
2.
The switch LEDs blink after about 2 seconds. If the switch is not configured, the LEDs above the
Mode button turn green. You can omit the next step.