Nortel 4526T-PWR 安装指南
58
Installing the Nortel Ethernet Routing Switch
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.
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.
two paths between units. If one path is interrupted, the data travels over the
remaining path at half the normal interswitch bandwidth.
shows a typical example of a stack
configuration reacting to a failed connection in the stack configuration.
Redundant cascade stacking
1. Base Unit
2. Last Unit
3. Unit selector switch
4. Cascade Cable
In the example, the following occur:
•
Unit 3 becomes non-operational due to a unit failure, cable
disconnection, or a loss of power.
disconnection, or a loss of power.
•
Units 2 and 4, directly upstream and downstream from Unit 3, sense
the loss of link signals from unit 3. The software directs all the data to
traverse the remaining path.
the loss of link signals from unit 3. The software directs all the data to
traverse the remaining path.
Nortel Ethernet Routing Switch 4500 Series
Installation Guide
NN47205-300 (322811-B)
03.01
Standard
5.1
19 November 2007
Copyright © 2007, Nortel Networks
.