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Connecting the EX9253 to External Devices

Connect a Device to a Network for Out-of-Band Management

Ensure that you have an Ethernet cable that has an RJ-45 connector at either end. Figure 1 shows the RJ-45 connector of the Ethernet cable supplied with the device.

Figure 1: RJ-45 Connector on an Ethernet CableRJ-45 Connector on an Ethernet Cable

You can monitor and manage these devices by using a dedicated management channel. Each device has a management port to which you can connect an Ethernet cable with an RJ-45 connector. Use the management port to connect the device to the management device.

To connect a device to a network for out-of-band management (see Figure 2):

  1. Connect one end of the Ethernet cable to the management port on the device.
  2. Connect the other end of the Ethernet cable to the management device.
Figure 2: Connect a Device to a Network for Out-of-Band ManagementConnect a Device to a Network for Out-of-Band Management

Connect a Device to a Management Console Using an RJ-45 Connector

Ensure that you have an Ethernet cable that has an RJ-45 connector at either end. One such cable and an RJ-45 to DB-9 serial port adapter are supplied with the device.

Figure 3 shows the RJ-45 connector of the Ethernet cable.

Figure 3: RJ-45 Connector on an Ethernet CableRJ-45 Connector on an Ethernet Cable
Note:

If your laptop or desktop PC does not have a DB-9 plug connector pin and you want to connect your laptop or desktop PC directly to the device, use a combination of the RJ-45 to DB-9 socket adapter supplied with the device and a USB to DB-9 plug adapter. You must provide the USB to DB-9 plug adapter.

You can configure and manage devices using a dedicated management channel. Each device has a console port which you can connect to using an Ethernet cable with an RJ-45 connector. Use the console port to connect the device to the console server or management console. The console port accepts a cable that has an RJ-45 connector.

To connect the device to a management console (see Figure 4 and Figure 5):

  1. Connect one end of the Ethernet cable to the console port (labeled CON, CONSOLE, or CON1) on the device.
  2. Connect the other end of the Ethernet cable to the console server (see Figure 4) or management console (see Figure 5).
Figure 4: Connect a Device to a Management Console Through a Console ServerConnect a Device to a Management Console Through a Console Server
Figure 5: Connect a Device Directly to a Management ConsoleConnect a Device Directly to a Management Console

Connecting the EX9253 Switch to External Clocking and Timing Devices

The switch supports external clock synchronization for Synchronous Ethernet and external inputs. The connections to the switch are made through the ports on the front panel. Figure 6 shows the ports that are used to connect the switch to external clocking and timing devices.

Figure 6: Ports Used to Connect the Switch to External Clocking and Timing DevicesPorts Used to Connect the Switch to External Clocking and Timing Devices
  1
—
Time-of-day (ToD) port with LED. Support for this port is not available in this release.
  3
—
10-MHz input and output timing ports
  2
—
BITS ports with LEDs
  4
—
1-PPS input and output timing ports

Connecting 1-PPS and 10-MHz Timing Devices to the Switch

The switch has four SubMiniature B (SMB) connectors that support 1-PPS and 10-MHz timing devices (see Figure 6).

Note:

Ensure that a cable of 3 m or less in length is used for the 10-MHz and 1-PPS connectors.

To connect the SMB coaxial cable to the external clocking input port:

  1. Connect one end of the SMB coaxial cable to either the socket labeled IN on the 1-PPS SMB connector or the 10-MHz SMB connector on the switch.
  2. Connect the other end of the SMB coaxial cable to the 1-PPS or 10-MHz source network equipment.
    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 6).

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

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.

  1. In configuration mode, go to the [edit chassis synchronization] hierarchy level.
  2. Configure the Synchronous Ethernet clock selection mode as auto-select or free-run to select the clock source either from an external qualified clock or from a free-run local oscillator.
  3. Enable Ethernet Synchronization Message Channel (ESMC) packet transmission on all interfaces or on a specific interface.
  4. Configure the hold interval as configuration-change, which is the wait time (from 15 seconds through 60 seconds) after a change in configuration; restart, which is the wait time (from 60 seconds through 180 seconds) after reboot of the switch; and switchover, which is the switchover wait time (from 30 seconds through 60 seconds) after clock recovery.
  5. Configure the EEC synchronization networking type as option-1 or option-2.
  6. Configure the quality-mode-enable statement to enable Synchronous Ethernet ESMC quality mode.
  7. Configure the selection mode for the incoming ESMC quality as configured-quality or received-quality. Specify the configured-quality option to enable the clock source selection algorithm to use the ESMC or SSM quality level that is configured for a qualifying interface or the received-quality option to use the ESMC or SSM quality that is received on the qualifying interface.
  8. Configure the switchover mode as revertive or non-revertive. The revertive option enables the device to automatically switch from a lower to a higher quality clock source whenever the higher clock source becomes available. On the other hand, the non-revertive option enables the device to continue using the current clock source as long as it is valid.
  9. Configure the options for the ESMC source related external clock source interface.
    1. Go to the [edit chassis synchronization source interfaces external] hierarchy level or the [edit chassis synchronization source interfaces ethernet-interface-name] hierarchy level.

      OR

    2. Configure the external clock interface and the Ethernet interface with their options. Configure the priority statement from 1 through 5; the quality-level statement as prc, prs, sec, ssu-a, ssu-b, st2, st3e, stu, or tnc; the request statement as force-switch or lockout; the wait-to-restore statement from 0 minutes to 12 minutes; and the hold-off-time statement from 300 through 1800 milliseconds. You can configure the same options for the Ethernet interfaces as well.
  10. Configure the options for the external interfaces.
    1. Go to the [edit chassis synchronization interfaces external] hierarchy level.
    2. Configure the frequency for the provided reference clock.
    3. For BITS interface, configure options for the e1 signal type— the framing statement as g704 or g704-no-crc, and the line-encoding statement as ami or hdb3.
    4. For BITS interface, configure options for the t1 signal type— the framing statement as esf or sf and the line-encoding statement as ami or b8zs.
  11. Configure the options for the external clock interface output.
    1. Go to the [edit chassis synchronization output interfaces external] hierarchy level.
    2. Configure all the external clock interface output options. The options include the holdover-mode-disable statement; the minimum-quality statement, which can be set as prc, prs, sec, ssu-a, ssu-b, st2, st3e, stu, or tnc; the source-mode statement, which can be set as chassis or line; the tx-dnu-to-line-source-enable statement; and the wander-filter-disable statement.

See Also