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Synchronize VUE server clocks using PTP
Last Updated: July 07, 2026

In a synchronous DAA environment, Precision Time Protocol (PTP) must be configured on all VUE application servers to synchronize the servers output transmit clocks with the receive clocks of the RPD/RMD devices. In an asynchronous DAA environment, if PTP is not configured then NTP must be configured. Either PTP or NTP must be configured on all VUE servers. The PTP service is deployed during installation and started with a sample configuration. If running in a synchronous DAA environment, you must modify the configuration based on your system and restart the service for proper operation.

PTP interface configuration

VUE application server operation with RPDs require PTP time synchronization with a Master Clock Time Server. The following PTP configuration requirements provide a framework for PTP operation on the VUE system.

  • Required on all VUE application servers communicating with RPDs.
  • Interface selection should be the servers network interface used to communicate with RPDs.
  • Selected interface for PTP configuration (typically IPv6) should be configured with a static IP address.
  • A static route specific to establish communication with the Master Clock Time Server should be defined within a route file on each VUE application server.

    Sample PTP static route configuration

    Assuming the following network parameters for this example:
    VUE application server selected interface
    eth5
    VUE App Server eth5 static IP address
    fc00:cb2:6:101:17::5
    Gateway IP address
    fc00:cb2:6:101:0::1
    PTP Master Clock IP address
    fe80::20c:29ff:fe83:edfd
    The above network parameters can be assembled to create a static route to the PTP Master Clock time server within a route file, route6-eth5 in this example, located in the /etc/sysconfig/network-scripts directory as follows:
    ::/fe80::20c:29ff:fe83:edfd/64 via fc00:cb2:6:101:0::1 dev eth5 src fc00:cb2:6:101:17::5
    NOTE: If the specific route6-ethX file (where X is the network interface number) for the desired VUE application server interface to establish PTP Master Clock communication does not exist then that route6-ethX file can be created to contain the route details.

PTP interface support verification

The network adapter used for IEEE1588 must support software time stamping. This can be verified using ethtool. The interface used for PTP reception must support software time stamping.

To verify time stamping support on the interface, run following command on the VUE application server:

$ ethtool -T ethX

where, ethX = eth1, eth2 and so on can be the interface names used for PTP.

An alternate method to verify software timestamp support is to inspect the hardware capabilities for PTP. You must have the software capabilities listed:

  • SOF_TIMESTAMPING_SOFTWARE
  • SOF_TIMESTAMPING_TX_SOFTWARE
  • SOF_TIMESTAMPING_RX_SOFTWARE

By default, the time_stamping is set to software.

Change time_stamping to hardware

To check whether the PTP configuration supports hardware timestamping. You must have the hardware capabilities listed.
$ sudo ethtool -T <interface-name>
For example:
$ sudo ethtool -T eth0
SOF_TIMESTAMPING_RAW_HARDWARE
SOF_TIMESTAMPING_TX_HARDWARE
SOF_TIMESTAMPING_RX_HARDWARE
If the VUE server has hardware PTP support and want to configure hardware PTP time stamping:
  1. Edit the file, /var/opt/vue-server/ptp/linuxPtp.conf.
  2. Change the time stamping PTP hardware:
    $ time_stamping   hardware
  3. Save and exit the file.
  4. Restart the PTP containers:
    $ sudo docker-compose -f /arris/compose/vue-ptp-compose.yml stop
$ sudo docker-compose -f /arris/compose/vue-ptp-compose.yml rm -f
$ sudo docker-compose -f /arris/compose/vue-ptp-compose.yml up -d
  5. Verify the PTP status.
    $ cat /var/opt/vue-server/ptp/linuxPtp.status

For more information see the section, System Requirements on http://linuxptp.sourceforge.net/.