Connecting A Bits External Clocking Device To The Switch; Configuring Clock Synchronization Interface On Ex9251 And Ex9253 Switches; Configuring Clock Synchronization Options - Juniper EX9253 Hardware Manual

NOTE: Ensure that the 1-PPS or 10-MHz source network equipment contains low voltage
complementary metal oxide semiconductor (LVCMOS) or is compatible with low-voltage
(3.3 V) transistor– transistor logic (LVTTL).

Connecting a BITS External Clocking Device to the Switch

The switch has an external building-integrated timing supply (BITS) port, labeled BITS, on the front panel
of the switch (see Figure 37 on page
To connect the switch to a BITS external clocking device:
1. Wrap and fasten one end of the ESD wrist strap around your bare wrist, and connect the other end
of the strap to the ESD point on the switch.
2. Plug one end of an RJ-45 cable into the internal clock port on the front panel.
3. Plug the other end of the RJ-45 cable into the BITS external clocking device.
4. Verify that the LEDs for the BITS port are lit steadily green.
5. Configure the port.
Configuring Clock Synchronization Interface on EX9251 and EX9253
Switches
IN THIS SECTION

Configuring Clock Synchronization Options | 95

Starting with Junos OS Release 18.1R1, EX9251 switches support external clock synchronization for
Synchronous Ethernet, T1 or E1 line timing sources, and external inputs. Starting with Junos OS Release
18.2R1, EX9253 switches support external clock synchronization for Synchronous Ethernet, T1 or E1
line timing sources, and external inputs. Configuring external clock synchronization requires making
clock selection, quality level, and priority considerations. The clock source selection algorithm is used to
pick the two best upstream clock sources from among the various sources on the basis of system
configuration and execution criteria such as quality level, priority, and hardware restrictions.
Configuring Clock Synchronization Options
To configure the clock synchronization options.
94).
95