NTP Server and Client

Document revision:1.1 (January 23, 2008, 14:31 GMT)
Applies to: V3.0

General Information


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. Note that if NTP client is all you need, you may want to consider using SNTP client instead for it has lower system requirements and significantly smaller memory footprint. It is included in the system package and is activated once ntp package is disabled or uninstalled.


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


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:


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: - specifies IP address of the primary NTP server

secondary-ntp (IP address; default: - 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)


To enable the NTP client to synchronize with the server:

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


Submenu level: /system ntp server

Property Description

broadcast (yes | no; default: no) - whether NTP broadcast message is sent to 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 and responds to them

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


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.


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>