Slots for line modules, switch route processor (SRP) modules, and switch fabric module (SFM) modules are located in the front of the router, while slots for input/output adapters (IOAs) and SRP IOAs are located in the rear.
Figure 12: E320 Router, Front View

Figure 13: E320 Router, Rear View

Figure 14: E120 Router, Front View

Figure 15: E120 Router, Rear View

For details about available line modules, IOAs, and compatibility between line modules and SRP modules, see the E120 and E320 Module Guide.
Slot numbering for the routers is similar.
Figure 16: E320 Slot Numbering

Figure 17: E120 Slot Numbering

Table 4: Module Slot Locations
Depending on the software release and IOA type, you must install IOAs in certain slots and bays combined with other IOAs in the same slot:
For information about working with modules and IOAs, see JUNOSe System Basics Configuration Guide, Chapter 6, Managing Modules. See Table 5 for currently available IOAs and the bays in which you may insert them.
Table 5: IOA Locations and Combinations
Line modules can only be paired with specific IOA, SFM, and SRP modules. See Table 6 for valid combinations.
Table 6: Module Combinations
Small form-factor pluggable transceivers (SFPs) are used on most IOAs. A range of SFPs that support different optical modes (multimode and single mode) and cabling distances are available. You can replace SFPs without disabling the interface or removing the module from the system. See Installing and Removing SFPs for more information and the E120 and E320 Module Guide for IOAs that use SFPs.
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Note: Because SFPs are the same shape and size, you are able to insert an SFP that is not compatible with the IOA. Be sure the SFP you are installing is appropriate for the interface you are plugging it into. If you insert the wrong SFP, software diagnostics detect the error. |
Use extra caution when handling an ES2 4G LM so that you do not damage module components or dislodge the heat sinks.
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Note: When lifting, carrying, or holding the module, do not grasp it near the six heat sinks along the top and bottom edge of the module. Instead, hold the module along the faceplate and the edges, keeping your fingers and thumbs away from all components. Do not use either row of heat sinks as a handle when carrying the module. You might dislodge or damage them. |
Figure 18: LM4 Heat Sink Locations

In a 100 Gbps fabric configuration, you must install the ES2 10G Uplink line module in slot 2 or slot 4 only.
Conversely, if you install a line module in slot 3 or slot 5 next to a previously installed ES2 10G Uplink module, the non-ES2 10G Uplink module will be disabled. For example, if you install an ES2 10G Uplink line module in both slot 2 and slot 4 in an E320 router, you can install the ES2 4G line module in the following locations: 0-1 and 6-11.
For information about software procedures associated with replacing and managing modules and IOAs, see JUNOSe System Basics Configuration Guide, Chapter 6, Managing Modules.
Before you attempt to install or replace a line module (inserted in the front of the chassis), make sure a compatible IOA (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 a compatible IOA module is not present, the diagnostics fail, and you need to remove and reinsert the line module.
The router supports hot-swapping of line modules and IOAs. Hot-swapping enables you to add or remove a line module without powering down the system. IOAs that support hot-swapping enable you to add or remove an IOA without rebooting the line module. See Table 5 for a list of hot-swappable IOAs.
The E320 router has two ESD (electrostatic discharge) grounding jacks. The front jack is located below the air filter bezel in the center of the router. The rear jack is located in the upper-right corner of the chassis. The E120 router has one ESD grounding jack located in the upper-right corner of the chassis in the rear. To prevent damage from electrostatic discharge, wear an antistatic wrist strap and connect it to one of the jacks when handling components.
To protect the modules, IOAs, and slots when installing components, observe the following guidelines:
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Caution: When handling components, use an antistatic wrist strap connected to one of the router's ESD grounding jacks. This action helps to protect the module from damage by electrostatic discharge. |
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Caution: Always handle a module by its edges. Do not touch the components, pins, leads, or solder connections. |
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Caution: If you meet strong resistance when attempting to seat a module using the ejectors, remove it from the chassis and confirm that the slot is designed to hold the module. Also, be sure that you have aligned the top and bottom edges in the correct matching card guides. |
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Caution: 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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Caution: Do not discard the antistatic bag. When a module is not in use, store it in an antistatic bag. |
You need the following tools to install a line module: