Cisco FASTHUB 412 12 PORT 10/100 STACKABLE Техническое Руководство

FastHub 400 10/100 Series Installation and Configuration Guide

You need at least one FastHub 400M model per three interconnected hubs (one hub stack)
if you want to manage the stack. A second FastHub 400M model in the stack can act as a
redundant stack manager in case the primary manager fails.

If a hub stack has more than one management hub, the upper management hub in the stack
is the primary management hub. The lower management hub is the secondary management
hub.

To manage the hub stack, you can use the system information (such as the IP, CDP, and
SNMP information) assigned to the primary management hub. The primary management
hub also stores the port settings of each hub in the stack. If the primary management hub
becomes inactive or is disconnected from the stack, the secondary management hub
becomes the primary management hub and uses the same stack information.

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If a stack has only one management hub and another management hub is added to the
stack, the system information from the management hub that has the longest system-up
time is used by the topmost management hub. This happens if the new management hub
is added either above or below the preexisting management hub.

•

If you replace the only management hub in the stack with a different management hub,
the stack will use the settings of the newly installed management hub.

If you are removing a management hub and there is no secondary management

hub in the stack, you lose manageability for the entire hub stack. In addition, if the removed
management hub is mounted between two operating hubs, you split the Ethernet segment
into two separate segments when the stacking cables are disconnected.

For information on managing the hub stack through the hub manager, see the “Managing
the Hub Segments” section on page 3-27.