You can set or change the Network Time Protocol (NTP) server on each Oracle Exadata Storage Server.

1. Log in to the cell as the root user.
2. Use the ipconf utility to change the NTP settings.
   1. Check to ensure there are no configuration issues with the new settings.

      Use the following command, where IP_addr_list is a comma-separated list of up to 3 IP addresses for the NTP servers. If you are also modifying the NTP servers for ILOM, then include the -ilom-ntp parameter and replace ILOM_NTP_list with a comma-separated list of up to 3 IP addresses for the NTP servers. Including the -dry parameter means the settings are checked, but not applied.

      Note:

      If you use host names for the NTP servers instead of IP addresses, then the cellwall service will fail when restarted. Use only IP addresses when defining NTP and DNS servers.

      # ipconf -update -ntp IP_addr_list [-ilom-ntp ILOM_NTP_list] -dry

   2. Update the NTP settings using the ipconf command:

      In the following command, IP_addr_list is a comma-separated list of up to 3 IP addresses for the NTP servers. If you also want to change the NTP servers for ILOM, then include the -ilom-ntp parameter and replace ILOM_NTP_list with a comma-separated list of up to 3 IP addresses for the NTP servers. Include the -force parameter to force the update, bypassing all checks.

      # ipconf -update -ntp IP_addr_list [-ilom-ntp ILOM_NTP_list] [-force]

      If the timestamp obtained from the new NTP server differs from the current time known to the system by more than 1 second (time step), then the command fails and does not update the NTP settings. You can use the -force option with the command line to override this check.

      Here is an example of the command and its output.

      [root@dbm03adm02 oracle.cellos]# ipconf -update -ntp 10.31.138.20,10.31.16.1 
      -ilom-ntp 10.31.138.20,10.31.16.1
      [Info]: ipconf command line: ipconf -update -ntp 10.31.138.20,10.31.16.1 
      -ilom-ntp 10.31.138.20,10.31.16.1
      Logging started to /var/log/cellos/ipconf.log
      [Info]: Updating dns/ntp
      [Warning]: ntpd service is not running
      [Info]: Backup existing cell configuration file /opt/oracle.cellos/cell.conf to 
      /var/log/exadatatmp/cell.conf_2020_01_13-17_54_56
      [Info]: Restart ntpd service
      Shutting down ntpd:                                        [  OK  ]
      Starting ntpd:                                             [  OK  ]
      [Done]: Update cell configuration file /opt/oracle.cellos/cell.conf OK