Juniper Networks MX240 manual Routing Engine Interface Ports, Routing Engine Boot Sequence

MX240 Ethernet Services Router Hardware Guide

Table 10: Routing Engine LEDs

Label	Color	State	Description
MASTER	Blue	On steadily	Routing Engine is the Master.
HDD	Green	Green	Hard disk is functioning normally.
		blinking
ONLINE	Green	Blinking	Routing Engine is transitioning online.
		On steadily	Routing Engine is functioning normally.
FAIL	Red	On steadily	Routing Engine has failed.

Routing Engine Interface Ports

Three Routing Engine ports connect the Routing Engine to one or more external devices on which system administrators can issue JUNOS command-line interface (CLI) commands to manage the router (see Figure 9 on page 14).

The ports with the indicated labels function as follows:

■AUX—Connects the Routing Engine to a laptop, modem, or other auxiliary device through a serial cable with an RJ-45 connector.

■CONSOLE—Connects the Routing Engine to a system console through a serial cable with an RJ-45 connector.

■ETHERNET—Connects the Routing Engine through an Ethernet connection to a management LAN (or any other device that plugs into an Ethernet connection) for out-of-band management. The port uses an autosensing RJ-45 connector to support 10-Mbps or 100-Mbps connections. Two small LEDs on the top of the port indicate the connection in use: the LED flashes yellow or green for a 10-Mbps or 100-Mbps connection, and the LED is light green when traffic is passing through the port.

For information about the pinouts for the connectors, see “Cable Connector

Pinouts” on page 185.

Routing Engine Boot Sequence

The Routing Engine boots from the storage media in this order: the USB device (if present), then the CompactFlash card, then the hard disk, then the LAN.

If the Routing Engines are configured for nonstop routing and graceful switchover, the backup Routing Engine automatically synchronizes its configuration and state with the master Routing Engine. Any update to the master Routing Engine state is replicated on the backup Routing Engine. If the backup Routing Engine assumes mastership, packet forwarding continues through the router without interruption. For more information about graceful switchover, see the JUNOS High Availability Configuration Guide.

16■ Host Subsystem