Connecting The Acx500 Router To External Clocking Devices; Connecting 1 Pps Timing Devices To The Router; Configuring Junos Os On The Acx500 Router - Juniper ACX500 Hardware Manual

Connecting the ACX500 Router to External Clocking Devices

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Connecting 1 PPS Timing Devices to the Router | 179

The ACX500 routers support external clock synchronization for Synchronous Ethernet, and external
inputs.
Connecting 1 PPS Timing Devices to the Router
The two SubMiniature B (SMB, 1 PPS input and 1 PPS output) connectors on the front panel of the
router connect to external clock signal sources.
To connect the SMB coaxial cable to the external clocking input port:
1. Connect one end of the SMB coaxial cable to the 1 PPS SMB connector on the router.
2. Connect the other end of the SMB coaxial cable to the 1 PPS source network equipment.
SEE ALSO
External Clocking Ports Specifications on ACX500 Routers | 106
Troubleshooting Resources for ACX500 Routers | 197

Configuring Junos OS on the ACX500 Router

The ACX500 routers are shipped with Junos OS preinstalled and ready to be configured when the router
is powered on. One 4-GB internal NAND flash memory device is divided into two partitions (da0s1 and
da0s2). One partition is marked as the active partition, and the other partition functions as an alternate
partition. The NAND flash device acts as the hard drive. One USB port on the front panel accepts a USB
storage device (usb0) that can also function as an alternate boot device.
When the router boots, it first attempts to start the image on the USB flash memory device. If a USB
flash memory device is not inserted into the router or the attempt otherwise fails, the router next tries
the active partition on the NAND flash device, and then tries the alternate partition on the NAND flash
device.
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