IDPA: Understanding Network Time Protocol Commands

Check if the Network Time Protocol (NTP) is configured on IDPA systems by running the below command. The "Network time on" line shows if NTP is on or off. The "NTP synchronized" line shows if NTP is synchronized. 

timedatectl status 
acm-4400-crk-2:~ # timedatectl status
      Local time: Tue 2024-02-06 15:33:39 GMT
  Universal time: Tue 2024-02-06 15:33:39 UTC
        RTC time: Tue 2024-02-06 15:33:39
       Time zone: America/Danmarkshavn (GMT, +0000)
 Network time on: yes
NTP synchronized: yes
 RTC in local TZ: no

The below command gives you information about time servers' set up. It also shows the offset from the NTP server and the local server. 

ntpq 
acm-4400-crk-2:~ # ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*10.60.9.97      10.104.0.254     2 u  628 1024  377    0.599  +22.417  41.474

REMOTE: The localhost plus peer hosts specified in the configuration files, from which your host takes time synchronization.

• Character that may be before hostname:
• * Indicates the current synchronization source.
• # Indicates that the host is selected for synchronization, but the distance from the host to the server exceeds the maximum value.
• o Indicates that the host is selected for synchronization, and the PPS signal is in use.
• + Indicates that the host in the final synchronization selection set.
• x Indicates that the host is the designated false ticker by the intersection algorithm.
• . Indicates that the host is selected from the end of the candidate list
• - Indicates a host discarded by the clustering algorithm.
• Blank indicates that a host is discarded due to high stratum and or failed sanity checks.

REFID - The current source of synchronization for the remote host

STRATUM - The stratum level of the remote host

• NTP uses the concept of a "stratum" to describe how many NTP "hops" away a machine is from an authoritative time source. A "stratum 1" time server typically has an authoritative time source (such as a radio or atomic clock, or a GPS time source) directly attached, a "stratum 2" time server receives its time by NTP from a "stratum 1" time server, and so on. 

T - Types that are available.

• l Local (such as a GPS clock)
• u Unicast (this is the most common type)
• m Multicast
• b Broadcast
• - Netaddr (usually 0)
• WHEN - The number of seconds passed since the remote host response
• POLL - Polling interval to the remote host, defined with the "minpoll" value in the ntp.conf file
• REACH - Indicates how successful attempts to reach the server are
  • This is an 8-bit shift register with the most recent probe in the 2^0 position.
  • The value 001 indicates that the most recent probe was answered.
  • The value 357 indicates that one probe was not answered.
  • The value 377 indicates that all the recent probes have been answered.

DELAY - (round-trip time) indicates the time (in milliseconds) taken by the reply packet to return in response to a query sent by the server.

OFFSET - Indicates the time difference (in milliseconds) between the server's clock and the client's clock.

• When this number exceeds 128, and the message synchronization lost appears in the log file.

Jitter - Show the latest jitter (or estimated error) in milliseconds.

• The jitter associated with a timing reference indicates the magnitude of variance, or dispersion, of the signal. Different timing references have different amounts of jitter. The more accurate a timing reference, the lower the jitter value

To set time with the NTP server, run the following command with the IP of the NTP server.

ntpdate 10.60.9.97