Contents
vii
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Hardware Loopback 5-29
Hardware Loopback Example: LINK OK event 5-29
Hardware Loop Example: LINK NOT OK Event 5-30
Finding a Disconnected Cable 5-31
Fixing a Bad Connection Between StackWise Ports 5-32
CHAPTER
6Clustering Switches 6-1
Understanding Switch Clusters 6-1
Cluster Command Switch Characteristics 6-3
Standby Cluster Command Switch Characteristics 6-3
Candidate Switch and Cluster Member Switch Characteristics 6-4
Planning a Switch Cluster 6-5
Automatic Discovery of Cluster Candidates and Members 6-5
Discovery Through CDP Hops 6-6
Discovery Through Non-CDP-Capable and Noncluster-Capable Devices 6-7
Discovery Through Different VLANs 6-7
Discovery Through Different Management VLANs 6-8
Discovery Through Routed Ports 6-9
Discovery of Newly Installed Switches 6-10
HSRP and Standby Cluster Command Switches 6-11
Virtual IP Addresses 6-12
Other Considerations for Cluster Standby Groups 6-12
Automatic Recovery of Cluster Configuration 6-13
IP Addresses 6-14
Hostnames 6-14
Passwords 6-14
SNMP Community Strings 6-15
Switch Clusters and Switch Stacks 6-15
TACACS+ and RADIUS 6-17
LRE Profiles 6-17
Using the CLI to Manage Switch Clusters 6-17
Using SNMP to Manage Switch Clusters 6-18
CHAPTER
7Administering the Switch 7-1
Managing the System Time and Date 7-1
Understanding the System Clock 7-1
Understanding Network Time Protocol 7-2
Configuring NTP 7-4
Default NTP Configuration 7-4