Nortel 4526FX, Руководство по установке

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Nortel Ethernet Routing Switch 4500 series stacking 57
3. Cascade Cable (connected from Unit 2 Cascade Down connector to
Base Unit Cascade Up Connector)
Initial installation unit number assignment
When you install the stack, the software automatically determines the
physical order of all units in the stack according to the position of the base
unit within the stack. Thereafter, the individual units maintain their original
unit numbering, even if you change the position of one or more units in
the stack.
For example, when you initially power the stack, the base unit becomes unit
1 and the unit that the base unit connects to (across the Cascade Down
cable) becomes unit 2. The next unit is designated as unit 3, and so on, until
the maximum stack configuration (up to eight units) is reached. If another
unit in the stack is designated as the base unit, the new base unit keeps
its originally designated unit number in the stack.
Stack MAC address
When a switch participates in a stack configuration, a stack MAC address is
automatically assigned during stack initialization. The stack MAC address is
the base unit MAC address plus 1. If another unit in the stack is assigned
as the base unit, the new stack MAC address is the MAC address of the
new base unit plus 1. The original stack IP address still applies to the new
base unit.
Temporary base unit
If an assigned base unit fails, the next unit in the stack order automatically
becomes the new temporary base unit. The LED display on the front panel
of the temporary base unit changes to a steady amber state to indicate the
change. When this happens, use the Unit Select switch to designate the
temporary base unit as the base unit until you repair or replace the failed
base unit.
You must designate a base unit because the automatic failover is only
a temporary safeguard and, if the original unit rejoins the stack, it does
not resume base unit status. Also, if the stack configuration loses power,
the temporary base unit does not resume base unit status when power
is restored.
ATTENTION
If the temporary base unit is not assigned as the new base unit, and the temporary
base unit fails, the next unit in the stack order becomes the temporary base
unit. This process continues after successive failures until only two units are left
in the stack.
Nortel Ethernet Routing Switch 4500 Series
Installation Guide
NN47205-300 (322811-B) 03.01 Standard
5.1 19 November 2007
Copyright © 2007, Nortel Networks
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