Clock Synchronization Configuration

Clock Synchronization configuration involves global and interface-level settings.

ptp hierarchy
Figure 1. Clock Synchronization Configuration Hierarchy

Global Configuration

These commands configure the global clock Synchronization settings for the system.

Syntax:

set system ptp clock <options>

Attribute Description:

Attribute Description

clock g8275.1

Enables ITU-T G.8275.1 clock profile for PTP.

As per ITU-T G.8275.1 profile, the default domain value for the PTP is 24.

clock g8275.1 mode (slave | boundary)

Configures the PTP clock to operate in slave or boundary mode.

slave: The device synchronizes its local clock to an upstream master.

boundary:The device acts as both a slave (upstream) and a master (downstream), relaying and conditioning timing information.

two-step enable

Enables two-step PTP synchronization in which the device’s PTP clock to use two-step synchronization rather than one-step synchronization. In two-step synchronization mode, the device first sends a Sync message, captures the exact hardware transmission timestamp, and then immediately sends that timestamp in a separate Follow_Up message.

one-pps-out tod enable

Enables one-PPS output with TOD functionality. When enabled, the device outputs a 1PPS signal with ToD information via the RJ45 port, providing a means to verify that the clock is correctly frequency-locked and phase-aligned.

The example below shows the configuration for enabling PTP (Precision Time Protocol) in slave mode using the g8275.1 profile.

set system ptp clock g8275.1 mode slave
supervisor@rtbrick.net: cfg> show config system ptp
{
  "rtbrick-config:ptp": {
    "clock": [
      {
        "profile": "g8275.1",
        "mode": "slave"
      }
    ]
  }
}

The example below shows the configuration for enabling PTP (Precision Time Protocol) in boundary mode using the g8275.1 profile.

set system ptp clock g8275.1 mode boundary
supervisor@rtbrick.net: cfg> show config system ptp
{
  "rtbrick-config:ptp": {
    "clock": [
      {
        "profile": "g8275.1",
        "mode": "boundary"
      }
    ]
  }
}

Interface-level Configuration

These commands enable and configure PTP on specific network interfaces.

Syntax:

set interface <interface-name> <attribute> <value>

Attribute Description

<interface-name>

Name of the network interface.

ptp enable true

Enables (true) clock synchronization for the specified interface

synce enable true

Enables (true) synchronous Ethernet for the specified interface

synce esmc source output

Defines the source for the ESMC messages to be output by the interface.

synce esmc transmit-quality

Sets the base configuration for how the interface communicates quality levels (QL) via ESMC to downstream devices.

synce esmc transmit-quality dnu-force

Configures the interface to advertise a "Do Not Use" (DNU) quality level, effectively preventing downstream devices from using this interface as a timing source.

After the clock module is enabled and the clock is configured on the device, you can enable ptp, synce, and synce esmc on the network interface.

The following configuration enables PTP on the network interface named "ifp-0/1/66".

set interface ifp-0/1/66
set interface ifp-0/1/66 ptp enable true
supervisor@rtbrick.net: cfg> show config interface ifp-0/1/66
{
  "rtbrick-config:interface": [
    {
      "name": "ifp-0/1/66",
      "ptp": {
        "enable": "true"
      }
    }
  ]
}

The following configuration enables synce on the network interface named "ifp-0/1/66".

set interface ifp-0/1/66
set interface ifp-0/1/66 sync enable true
supervisor@rtbrick.net: cfg> show config interface ifp-0/1/66
{
  "rtbrick-config:interface": [
    {
      "name": "ifp-0/1/66",
      "sync": {
        "enable": "true"
      }
    }
  ]
}

The following configuration enables synce esmc on the network interface named "ifp-0/1/66".

set interface ifp-0/1/66
set interface ifp-0/1/66 sync synce esmc true
supervisor@rtbrick.net: cfg> show config interface ifp-0/1/66
{
  "rtbrick-config:interface": [
    {
      "name": "ifp-0/1/66",
      "sync": {
        "esmc": "true"
      }
    }
  ]
}

PTP and SyncE ESMC Destination MAC Configuration

You can configure the destination MAC for outgoing SyncE ESMC and PTP packets. The following CLI commands allow you to configure the destination MAC address for SyncE ESMC packets.

Syntax:

set system synce esmc destination-mac-address <destination-mac-address>

set system ptp global destination-mac-address <destination-mac-address>

Attribute Description

<destination-mac-address>

Specifies the destination MAC address for outgoing SyncE and PTP packets.

If no destination MAC address is configured, the system will use the default MAC address.

The following example sets the destination MAC address for SyncE ESMC packets to 01:80:C2:00:00:02.

set system synce esmc destination-mac-address 01:80:C2:00:00:02
{
  "rtbrick-config:system": {
    "synce": {
      "esmc": {
        "destination-mac-address": "01:80:C2:00:00:02"
      }
    }
  }
}

The following example sets the destination MAC address for PTP packets to 01:1B:19:00:00:00.

set system ptp global destination-mac-address 01:1B:19:00:00:00
{
  "rtbrick-config:system": {
    "ptp": {
      "global": {
        "destination-mac-address": "01:1B:19:00:00:00"
      }
    }
  }
}

Configuring SyncE Input Source for PTP Interfaces

You can configure whether a specific PTP interface serves as the physical frequency input source for SyncE.

Syntax:

set system synce interface-ptp input-source ( disable |enable )

Attribute Description

input-source (disable | enable)

Specifies whether the PTP interface is used as the physical SyncE frequency input source. Set to enable to use the interface as the SyncE input source, or disable to stop using it as the SyncE input source. By default, this is enabled.