Cisco 6500 - Manual (Page 20)

4-20
Cisco IOS Software Configuration Guide, Release 12.2SX
OL-13013-06
Chapter 4 Configuring Virtual Switching Systems
Understanding Virtual Switching Systems
Software Features
Software features run only on the VSS active supervisor engine. Incoming packets to the VSS standby
chassis that require software processing are sent across the VSL.
For features supported in hardware, the ACL configuration is sent to the TCAM manager on the VSS
active supervisor engine, the VSS standby supervisor engine, and all DFCs.
SPAN
The VSS supports all SPAN features for non-VSL interfaces. The VSS supports SPAN features on VSL
interfaces with the following limitations:
• If the VSL is configured as a local SPAN source, the SPAN destination interface must be on the same
chassis as the source interface.
• VSL cannot be configured as a SPAN destination.
• VSL cannot be configured as a traffic source of RSPAN, ERSPAN, or egress-only SPAN.
The number of SPAN sessions available to a VSS is the same as for a single chassis running in standalone
mode.
System Monitoring
The following sections describe system monitoring and system management for a VSS:
• Power Management, page 4-20
• Environmental Monitoring, page 4-20
• File System Access, page 4-21
• VSL Diagnostics, page 4-21
• Service Modules, page 4-21
• Network Management, page 4-22
Power Management
From the VSS active chassis, you can control power-related functions for the VSS standby chassis. For
example, use the power enable switch command to control power to the modules and slots on the VSS
standby chassis. Use the show power switch command to see the current power settings and status.
Environmental Monitoring
Environmental monitoring runs on both supervisor engines. The VSS standby chassis reports
notifications to the VSS active supervisor engine. The VSS active chassis gathers log messages for both
chassis. The VSS active chassis synchronizes the calendar and system clock to the VSS standby chassis.