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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
Chapter 31 Troubleshooting
Preventing Autonegotiation Mismatches
Step 10 When prompted for the enable secret and enable passwords, enter the passwords of the failed command
switch again.
Step 11 When prompted, make sure to enable the switch as the cluster command switch, and press Return.
Step 12 When prompted, assign a name to the cluster, and press Return.
The cluster name can be 1 to 31 alphanumeric characters, dashes, or underscores.
Step 13 When the initial configuration displays, verify that the addresses are correct.
Step 14 If the displayed information is correct, enter Y, and press Return.
If this information is not correct, enter N, press Return, and begin again at Step 9.
Step 15 Start your browser, and enter the IP address of the new command switch.
Step 16 From the Cluster menu, select Add to Cluster to display a list of candidate switches to add to the cluster.

Recovering from Lost Member Connectivity

Some configurations can prevent the command switch from maintaining contact with member switches.
If you are unable to maintain management contact with a member, and the member switch is forwarding
packets normally, check for these conflicts:
• A member switch (Cisco Systems Intelligent Gigabit Ethernet Switch Module, Catalyst 3550,
3500 XL, 2955, 2950, 2940, 2900 XL, 2820, and 1900) cannot connect to the command switch
through a port that is defined as a network port.
• Catalyst 3500 XL, Catalyst 2900 XL, Catalyst 2820, and Catalyst 1900 member switches must
connect to the command switch through a port that belongs to the same management VLAN.
• A member switch (Cisco Systems Intelligent Gigabit Ethernet Switch Module, Catalyst 3550,
Catalyst 3500 XL, Catalyst 2950, Catalyst 2940, Catalyst 2900 XL, Catalyst 2820, and Catalyst
1900) connected to the command switch through a secured port can lose connectivity if the port is
disabled because of a security violation.
Preventing Autonegotiation Mismatches
The IEEE 802.3ab autonegotiation protocol manages the switch settings for speed (10 Mbps, 100 Mbps,
and 1000 Mbps excluding GBIC 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:
• 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.
To maximize switch performance and ensure a link, follow one of these guidelines when changing the
settings for duplex and speed:
• Let both ports autonegotiate both speed and duplex.
• Manually set the speed and duplex parameters for the ports on both ends of the connection.