Sync Time from an External Time Source

This is a quick post to how to sync your domain controllers with an external time source (0.uk.pool.ntp.org). By default, all machines in a domain will sync time from the domain controller which is the internal time server- if you have more then one Dc then time will sync from the DC that holds the PDC emulator FSMO role. To Check which DC is PDC emulator in your domain you need to run netdom /query fsmo command like so:

Once PDC emulator role is established there is a few commands we need to run in order for time to sync, these are (run on PDC emulator)

w32tm /config /manualpeerlist:"0.uk.pool.ntp.org" /syncfromflags:manual /reliable:yes /update
w32tm /config /update
net stop w32time && net start w32time

If you need to add more than one NTP server than the peer list entries are space delimited, see example below.

"0.uk.pool.ntp.org 1.uk.pool.ntp.org ntp2a.mcc.ac.uk"

Once completed windows time service should begin Synchronizing time on the domain controller(s) with the external source. to view the time configuration you can use w32tm /query /configuration command.

before synced with the external time server

and after I made the changes

all was set to sync from 0.uk.pool.ntp.org. From workstation point of view to configure a client computer for automatic domain time synchronization:

w32tm /config /syncfromflags:domhier /update

and to check if its syncing:

w32tm /monitor

and to re-sync:

w32tm /resync

If there’re any errors then these will be written to event Viewer – please check if you’re having issues

UK Time Servers

0.uk.pool.ntp.org
1.uk.pool.ntp.org
ntp2a.mcc.ac.uk
ntp2b.mcc.ac.uk
ntp2c.mcc.ac.uk
ntp2d.mcc.ac.uk
ntp.exnet.com