Set the NTP Server Address on the Database Servers

4.12.1 Set the NTP Server Address on the Database Servers

You can set or change the Network Time Protocol (NTP) server address on the database server of Oracle Exadata.

If you are using Oracle Exadata System Software 20.1.0 or later, use ipconf to set or change the NTP server.
1. Log in to the database server as the root user.
2. Check to make sure there are no configuration issues with the new settings.
  
  Use the following command, where IP_addr_list is a comma-separate list of 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-separate list of up to 2 IP addresses for the NTP servers. Including the -dry parameter means the settings are checked, but not applied.
```
# ipconf -update -ntp IP_addr_list [-ilom-ntp ILOM_NTP_list] -dry
```
3. Update the NTP settings using the following ipconf command:
  
  In the following command, IP_addr_list is a comma-separate list of 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-separate 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 errors out 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
```
4. Repeat these steps for each database server.
If the database server operating system is Oracle Linux 7 but using Oracle Exadata System Software 19.3.x or earlier, follow these instructions:
1. Stop the time synchronization service on the database server.
```
# systemctl stop chronyd
```
2. Update the /etc/chrony.conf file with the IP address of the new NTP server.
3. Start the time synchronization service on the database server.
```
# systemctl start chronyd
```
4. Repeat Steps 2.a through 2.c for each database server.
If the database server operating system is Oracle Linux 5 or 6:
1. Stop the NTP services on the database server.
```
# service ntpd stop
```
2. Update the ntp.conf file with the IP address of the new NTP server.
3. Start the NTP services on the database server.
```
# service ntpd start
```
4. Repeat Steps 3.a through 3.c for each database server.

Parent topic: Changing the NTP Servers