A spare line module provides redundancy for a group of identical line modules for ERX-7xx and ERX-14xx models only.
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Note: The ERX-310 router does not support line module redundancy. |
For line module redundancy to operate, you must install:
For more information, see Redundancy Features.
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Warning: Do not insert any metal object, such as a screwdriver, or place your hand into an open slot or the backplane when the router is on. Remove jewelry (including rings, necklaces, and watches) before working on equipment that is connected to power lines. These actions can prevent electric shock and serious burns. |
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Caution: When handling modules, use an antistatic wrist strap connected to the router's ESD grounding jack, and hold modules by their edges. Do not touch the components, pins, leads, or solder connections. These actions help to protect modules from damage by electrostatic discharge. |
To install the line modules in a redundancy group:
To install the redundancy midplane in a redundancy group:
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Caution: If you do not use the halt command before removing or powering down an SRP, the system's NVS card can become corrupted. |
See JUNOSe System Basics Configuration Guide, Chapter 6, Managing Modules for information about the halt command.
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Warning: Turn off the router before you install the redundancy midplane. Working inside the router when it is on can lead to electric shock and serious burns. |
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Caution: A misaligned redundancy midplane can result in bent pins on the backplane and midplane and poor contact between the I/O modules and the redundancy midplane. |
Figure 22: Installing a Redundancy Midplane

To install the I/O modules in a redundancy group:
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Caution: When setting up a redundancy group with line modules, be sure to install the redundancy I/O module in the lowest-numbered slot of the redundancy group. It is possible to install the redundancy I/O module in other slots; however, doing so can damage other I/O modules connected to the redundancy midplane. |
To verify that the installation is complete:
The system reboots.