Nortel Ethernet Routing Switch 4500 series stacking
47
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.
Note: 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.
Redundant cascade stacking
The Nortel Ethernet Routing Switch 4500 Series allows a stack of up to
eight units into a dual-path cascade stack. If any single unit fails, or if a
cable is accidently disconnected, other units in the stack remain operational.
In addition to increasing bandwidth, the software uses the cables to provide
two paths between units. If one path is interrupted, the data travels over the
remaining path at half the normal interswitch bandwidth.
"Redundant cascade stacking" (page 48)
shows a typical example of a stack
configuration reacting to a failed connection in the stack configuration.
Nortel Ethernet Routing Switch 4500 Series
Installation Guide
NN47205-300
02.01
Standard
5.0
23 February 2007
Copyright © 2007, Nortel Networks
Nortel Networks Confidential
.
Summary of Contents for 4500 Series
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