Juniper EX8208 Hardware Manual page 79

NOTE: We recommend that you install two SRE modules for redundancy. If you install only one
SRE module, we recommend that you install it in slot SRE0. See
Switch" on page 40.
If two SRE modules are installed, one functions as the primary and the other acts as the backup. If the
primary SRE module fails or is removed, the backup takes over as the primary.
If two SRE modules are installed, the backup SRE module is hot-insertable and hot-removable, but the
primary SRE module is hot-pluggable. If only one SRE module is installed, you must halt the SRE module
before removing it.
The SRE module provides these functions:
Provides full fabric connectivity to all line cards installed in the chassis
Through the switching plane, provides switching functionality to the switch
Powers the line cards on and off
Controls system resets and boot sequence for the switch
Monitors and controls the fan speed, power status for various chassis components, LCD panel and
chassis status LEDs
The SRE module has these components:
SRE module LEDs—Indicate system status. See
Recessed reset button—Power cycles the SRE module when pressed.
Take the SRE module offline using the CLI before pressing the reset button. See
Offline in an EX8208 Switch" on page
USB port—Provides an interface through which you can install the Junos OS manually. See
Specifications for an EX Series Switch" on page
Auxiliary port—This port is not enabled on the EX8200 switch. It is reserved for future use.
Console port—Connects the SRE module to a system console through a cable with an RJ-45 connector.
See "Connect a Device to a Management Console Using an RJ-45 Connector" on page
Management port—Connects the SRE module through an Ethernet connection to a management LAN
(or any other device that plugs into an Ethernet connection) for out-of-band management. See
a Device to a Network for Out-of-Band Management" on page
Ejector levers—Used for installing and removing the SRE module.
Captive screws—Secure the SRE module in place.
"SRE Module LEDs in an EX8208 Switch" on page
251.
136.
"Slot Numbering for an EX8208
"Taking the SRE Module
183.
182.
79
80.
"USB Port
"Connect