NTP users are strongly urged to take immediate action to ensure that their NTP daemon is not susceptible to use in a reflected denial-of-service (DRDoS) attack. Please see the NTP Security Notice
for vulnerability and mitigation details, and the Network Time Foundation Blog
for more information. (January 2014) See StartingNTPDev for discussion of this topic.
7. Starting NTP
7.2. How is NTP started?
On Unix-like operating systems NTP is started by an
script. If you are installing a pre-packaged version of NTP, the
script infrastructure may be pre-configured for you. If you are installing directly from the source you may have to manually configure your
system to start NTP at boot time.
7.3. When should NTP be started?
NTP should be started early in the boot process: after the network and DNS (if you are using any names instead of IP addresses for your servers/peers) are configured, but before any time-sensitive services are started.