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CHAPTER 1
The process by which the system switches to the spare line module is called switchover. When switchover occurs, the system:
1Breaks the connection between the primary I/O module and the primary line module.
2Connects the primary I/O module to the spare line module via the redundancy midplane and redundancy I/O module.
Protocol processing then takes place on the spare line module.
Figure 1-15 shows the data flow when a spare line module becomes active.
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Spare line module
Primary line module
Redundancy |
| g013738 | |
I/O module | Primary | ||
|
Ž | I/O module | |
Œ | ||
| ||
| Midplane |
Redundancy midplane
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1. A packet arrives at the primary I/O module.
2.The packet passes along the redundancy midplane from the primary I/O module to the redundancy I/O module.
3.The packet passes from the redundancy I/O module to the spare line module.
4.The spare line module processes the packet.