Rebooting would sync the clocks but its not necessary.
If you wanted to sync the clocks manually you can do the following:
# Sync the system time with NTP:
service ntpd stop
service ntpdate start
service ntpd start
# Check the hardware time
# Check the system time
# If the system time (date) is correct and there is a time difference with the hwclock
# If the hwclock is correct and there is a time difference with the system time
# Then check the times again
So if I changed the NTP from the Web console, as per below instruction
- Open Web Browser and go to the https://applianceIP:4712/ for each respective appliance.
- Go to Appliances Tab > expand Appliances container then click on the Date and Time and then change it into the new NTP server IP address.
- Click on [Save Changes] button on the top right hand corner
- Exit the setting page.
- Close the browser.
do I have to to do it from the SSH console as well ?
You don't have to do it from SSH, performing it from the GUI will do it as well.