System Clock and NTP

Document revision:NaN (Mon Jul 10 13:21:55 GMT 2006)
Applies to: V2.9

System Clock

Summary

System clock allows router to track current date and time.

Specifications

License required: Level1
Submenu level: /system clock

Property Description

date (text) - date in format "mm/DD/YYY"

dst-active (read-only: yes | no; default: no) - whether the Daylight Saving Time is currently acitve

time (time) - time in format "HH:MM:SS"

time-zone (text) - UTC timezone in format "+HH:MM" or "-HH:MM"

Notes

It is recommended that you reboot the router after time change to obviate the possible errors in time measurments and logging.

Date and time settings become permanent and effect BIOS settings.

If NTP update gives time shifted by 1 hour, although the time zone is set correctly, you may want to adjust the DST setting in /system clock dst menu.

Example

To view the current date and time settings:

[admin@Local] system clock> print
        time: 08:26:37
        date: nov/18/2004
   time-zone: +00:00
  dst-active: no
[admin@Local] system clock>

To set the system date and time:

[admin@Local] system clock> set date=nov/22/2022 time=11:10:21 time-zone=+0
[admin@Local] system clock> print
        time: 11:10:25
        date: nov/22/2022
   time-zone: +00:00
  dst-active: no
[admin@Local] system clock>

System Clock DST adjustment

Submenu level: /system clock dst

Description

In most countries, a Daylight Saving Time regime is activated in spring and deactivated in autumn. This configuration menu provides DST adjustment facility, to drift the timezone according to your local legislation and practice.

Property Description

dst-delta (text; default: +01:00) - UTC timezone drift in format "+HH:MM" or "-HH:MM" to be added to the local timezone during DST period

dst-end (date time) - date and time when DST ends (when the delta is to be dropped).

dst-start (date time) - date and time when DST begins (when the delta is to be applied).

Example

To make DST zonechange active from mar/27/2005 03:00:00 till oct/30/2005 03:00:00:

[admin@MikroTik] system clock dst> set dst-start="mar/27/2005 03:00:00" dst-end="oct/30/2005 03:00:00"
[admin@MikroTik] system clock dst> print
  dst-delta: +01:00
  dst-start: mar/27/2005 03:00:00
    dst-end: oct/30/2005 03:00:00
[admin@MikroTik] system clock dst>

General Information

Summary

NTP protocol allows synchronizing time among computers in network. It is good if there is an internet connection available and local NTP server is synchronized to correct time source. List of publec NTP servers is available at http://www.eecis.udel.edu/~mills/ntp/servers.html

Specifications

Packages required: ntp
License required: Level1
Submenu level: /system ntp
Standards and Technologies: NTP version 3 (RFC 1305)
Hardware usage: Not significant

Related Documents

Description

Network Time Protocol (NTP) is used to synchronize time with some NTP servers in a network. MikroTik RouterOS provides both - NTP client and NTP server.

NTP server listens on UDP port 123

NTP client synchronizes local clock with some other time source (NTP server). There are 4 modes in which NTP client can operate at:

Client

Submenu level: /system ntp client

Property Description

enabled (yes | no; default: no) - whether the NTP client is enabled or not

mode (unicast | broadcast | multicast | manycast; default: unicast) - NTP client mode

primary-ntp (IP address; default: 0.0.0.0) - specifies IP address of the primary NTP server

secondary-ntp (IP address; default: 0.0.0.0) - specifies IP address of the secondary NTP server

status (read-only: text) - status of the NTP client:
stopped - NTP is not running (NTP is disabled)
error - there was some internal error starting NTP service (please, try to restart (disable and enable) NTP service)
started - NTP client service is started, but NTP server is not found, yet
failed - NTP server sent invalid response to our NTP client (NTP server is not synchronized to some other time source)
reached - NTP server contacted. Comparing local clock to NTP server's clock (duration of this phase is approximately 30s)
timeset - local time changed to NTP server's time (duration of this phase is approximately 30s)
synchronized - local clock is synchronized to NTP server's clock. NTP server is activated
using-local-clock - using local clock as time source (server enabled while client disabled)

Example

To enable the NTP client to synchronize with the 159.148.60.2 server:

[admin@MikroTik] system ntp client> set enabled=yes primary-ntp=159.148.60.2
[admin@MikroTik] system ntp client> print
          enabled: yes
             mode: unicast
      primary-ntp: 159.148.60.2
    secondary-ntp: 0.0.0.0
           status: synchronized
[admin@MikroTik] system ntp client>

Server

Submenu level: /system ntp server

Property Description

broadcast (yes | no; default: no) - whether NTP broadcast message is sent to 255.255.255.255 every 64s

enabled (yes | no; default: no) - whether the NTP server is enabled

manycast (yes | no; default: yes) - whether NTP server listens for multicast messages sent to 239.192.1.1 and responds to them

multicast (yes | no; default: no) - whether NTP multicast message is sent to 224.0.1.1 every 64s

Notes

NTP server activities only when local NTP client is in synchronized or using-local-clock mode.

If NTP server is disabled, all NTP requests are ignored.

If NTP server is enabled, all individual time requests are answered.

CAUTION! Using broadcast, multicast and manycast modes is dangerous! Intruder (or simple user) can set up his own NTP server. If this new server will be chosen as time source for your server, it will be possible for this user to change time on your server at his will.

Example

To enable NTP server to answer unicast requests only:

[admin@MikroTik] system ntp server> set manycast=no enabled=yes
[admin@MikroTik] system ntp server> print
      enabled: yes
    broadcast: no
    multicast: no
     manycast: no
[admin@MikroTik] system ntp server>

Time Zone

Submenu level: /system clock

Notes

NTP changes local clock to UTC (GMT) time by default.

Example

Time zone is specified as a difference between local time and GMT time. For example, if GMT time is 10:24:40, but correct local time is 12:24:40, then time-zone has to be set to +2 hour:

[admin@MikroTik] system clock> print
         time: dec/24/2003 10:24:40
    time-zone: +00:00
[admin@MikroTik] system clock> set time-zone=+02:00
[admin@MikroTik] system clock> print
         time: dec/24/2003 12:24:42
    time-zone: +02:00
[admin@MikroTik] system clock>

If local time is before GMT time, time-zone value will be negative. For example, if GMT is 18:00:00, but correct local time is 15:00:00, time-zone has to be set to -3 hours:

[admin@MikroTik] system clock> set time-zone=-3
[admin@MikroTik] system clock> print
         time: sep/24/2004 08:13:28
    time-zone: -03:00
[admin@MikroTik] system clock>

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