Preventing Autonegotiation Mismatches; Sfp Module Security And Identification - Cisco WS-CBS3032-DEL Software Configuration Manual

Chapter 48 Troubleshooting
•
If you replace a stack member with an identical model, the new switch functions with the exact same
configuration as the replaced switch. This is also assuming the new switch is using the same member
number as the replaced switch.
Removing powered-on stack members causes the switch stack to divide (partition) into two or more
switch stacks, each with the same configuration. If you want the switch stacks to remain separate, change
the IP address or addresses of the newly created switch stacks. To recover from a partitioned switch
stack:
1.
2.
3.
For the commands that you can use to monitor the switch stack and its members, see the
Switch Stack Information" section on page

Preventing Autonegotiation Mismatches

The IEEE 802.3ab autonegotiation protocol manages the switch settings for speed (10 Mb/s, 100 Mb/s,
and 1000 Mb/s, excluding SFP module ports) and duplex (half or full). There are situations when this
protocol can incorrectly align these settings, reducing performance. A mismatch occurs under these
circumstances:
•
•
To maximize switch performance and ensure a link, follow one of these guidelines when changing the
settings for duplex and speed:
•
•
If a remote device does not autonegotiate, configure the duplex settings on the two ports to match. The
Note
speed parameter can adjust itself even if the connected port does not autonegotiate.

SFP Module Security and Identification

Cisco small form-factor pluggable (SFP) modules have a serial EEPROM that contains the module serial
number, the vendor name and ID, a unique security code, and cyclic redundancy check (CRC). When an
SFP module is inserted in the switch, the switch software reads the EEPROM to verify the serial number,
OL-13270-06
Manually assigning stack member numbers according to the placement of the switches in the stack
can make it easier to remotely troubleshoot the switch stack. However, if you add, remove, or
rearrange switches later, you need to remember that the switches have manually assigned numbers.
Use the switch current-stack-member-number renumber new-stack-member-number global
configuration command to manually assign a stack member number. For more information about
stack member numbers, see the
Power off the newly created switch stacks.
Reconnect them to the original switch stack through their StackWise Plus ports.
Power on the switches.
A manually set speed or duplex parameter is different from the manually set speed or duplex
parameter on the connected port.
A port is set to autonegotiate, and the connected port is set to full duplex with no autonegotiation.
Let both ports autonegotiate both speed and duplex.
Manually set the speed and duplex parameters for the ports on both ends of the connection.
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
"Stack Member Numbers" section on page
7-27.
Preventing Autonegotiation Mismatches
7-8.
"Displaying
48-9