Juniper SRX5400 - Page 92

Figure 43: Roung Engine
You must install at least one Roung Engine in the rewall. You can install a second Roung Engine if
both Roung Engines are running Junos OS Release 10.0 or later. A second Roung Engine is required if
you are using the dual chassis cluster control link feature available in Junos OS Release 10.0 and later.
The second Roung Engine does not perform all the funcons of a Roung Engine and does not improve
resiliency or redundancy. The second Roung Engine and the Switch Control Board (SCB) in which it is
installed do not constute a host subsystem. The only funcon of the second Roung Engine is to
enable the hardware infrastructure that enables the chassis cluster control 1 port on the Services
Processing Card (SPC) used for chassis cluster control links. If you install only one Roung Engine in the
rewall, you must install it in the slot in the front panel of SCB0. If you install a second Roung Engine to
use the dual chassis cluster control link feature, you install it in the slot in the front panel of SCB1.
The Roung Engine consists of the following components:
• CPU—Runs Junos OS to maintain the rewall's roung tables and roung protocols. It has a Penum-
class processor.
• DRAM—Provides storage for the roung and forwarding tables and for other Roung Engine
processes.
• USB port—Provides a removable media interface through which you can install Junos OS manually.
Junos supports USB version 1.0.
• Internal ash disk—Provides primary storage for soware images, conguraon les, and microcode.
The disk is a xed compact ash and is inaccessible from outside the rewall.
• Hard disk—Provides secondary storage for log les, memory dumps, and reboong the system if the
internal compact ash disk fails.
• HDD LED—Indicates disk acvity for the hard disk drive.
• Management ports—Each Roung Engine has one 10/100-Mbps Ethernet port for connecng to a
management network, and two asynchronous serial ports—one for connecng to a console and one
for connecng to a modem or other auxiliary device. The interface ports are labeled AUX, CONSOLE,
and ETHERNET.
88