Line module slots are located in the front of each ERX chassis, while I/O module slots are located in the rear. See ERX Overview for front and rear views of ERX routers.
In ERX-14xx models, modules mount vertically in a chassis with 14 slots. In ERX-7xx models and ERX-310 routers, modules mount horizontally in a chassis with 7 slots and 3 slots, respectively. See Figure 16.
Figure 16: Orientation of Line Modules in ERX Routers
For details about available line modules and compatibility between line modules and SRP modules, see the ERX Module Guide.
The slots in the ERX-1410 router and ERX-7xx models are divided into groups. The number of groups and number of slots per group depend on the system.
There are no slot groups in the ERX-1440 router or the ERX-310 router. In the ERX-310 router, slot 0 contains the SRP module and slots 1 and 2 each contain a line module.
A slot group in the ERX-1410 router comprises three adjacent chassis slots. The groups for the ERX-1410 router consist of the following slots (Figure 17):
Slots 6 and 7 are reserved for the SRP modules.
Figure 17: ERX-1410 Slot Groups
A slot group in an ERX-7xx model comprises one slot or two adjacent slots. The groups for an ERX-7xx model consist of the following slots (Figure 18):
Slots 0 and 1 are reserved for the SRP modules.
Figure 18: ERX-7xx Model Slot Groups
For information about combinations of line modules in slot groups, see JUNOSe System Basics Configuration Guide, Chapter 6, Managing Modules.
The ERX-1440 router with the SRP-40G+ SRP module supports OC48 line modules. Other ERX routers do not support OC48 line modules.
An OC48 line module spans two slots in an ERX-1440 router. You can install this line module only in slots 2–3 and slots 4–5. Other slots in the system do not support this line module.
The corresponding OC48 Frame APS I/O module spans only one slot. Install the I/O module in the lower of the slots (either slot 2 or slot 4) that the line module spans.
The ERX-1440 router with the SRP-40G+ SRP module supports GE-2 line modules in all slots; however, full bandwidth is delivered only when the line module is in slot 2 or slot 4. The line module can be used with other SRP modules, but maximum line performance will not be achieved.
The ERX-310 router with the SRP-SE10G SRP module supports GE-2 line modules in both slots (1 and 2). Maximum line performance is achieved in either slot.
Other ERX routers do not support GE-2 line modules.
For information about software procedures associated with replacing and managing modules, see JUNOSe System Basics Configuration Guide, Chapter 6, Managing Modules.
All ERX routers support hot-swapping of modules. Hot-swapping enables you to add or remove a module without powering down the system.
Each ERX chassis has an ESD (electrostatic discharge) grounding jack. See Table 4 for locations. To prevent damage from electrostatic discharge, connect an antistatic wrist strap to the jack when handling components.
Figure 19: Connecting the Wrist Strap to the ERX-310 Router (Rear)
Table 4: Grounding Jack Locations
To protect the modules and slots when installing modules, observe the following guidelines:
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When handling modules, use an antistatic wrist strap connected to the router's ESD grounding jack. This action helps to protect the module from damage by electrostatic discharge. |
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Always handle the module by its edges. Do not touch the components, pins, leads, or solder connections. |
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If you meet strong resistance when attempting to seat the module using the ejectors, remove it from the chassis and confirm that the slot is designed to hold the module. Then verify, if applicable, that the module matches its corresponding module (I/O module or line module). Also, be sure that you have aligned the top and bottom edges in the correct matching tracks. |
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Be sure to cover every empty slot with a blank filler panel to protect the system from dust or other foreign substances and to ensure proper system cooling. |
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Do not discard the antistatic bag. When a module is not in use, store it in an antistatic bag. |
Before you attempt to install or replace a line module (inserted in the front of the chassis), make sure the corresponding I/O module (inserted in the rear of the chassis) is already in place. The slot diagnostics run when a line module is installed in a chassis slot. If the corresponding I/O module is not present, the diagnostics fail, and you need to remove and reinsert the module.
You need the following tools to install a line module: