Log into the device with Telnet or SSH. Enter privileged mode by typing enable and entering your enable password.
Enable DNS lookup
Make sure DNS lookups are enabled on your device so it can be synced to an NTP server. Run the following command. Replace 8.8.8.8 8.8.4.4
with the DNS servers you’d like to use.
enable ip domain lookup ip name-server 8.8.8.8 8.8.4.4 exit
Set the clock, time zone, and NTP server
There are four locations shown as examples. To see the available global zones from NTP Pool, refer to https://www.ntppool.org/zone/@.
For each example, replace clock set 09:00:00 1 Jan 2018
with the current time and date at the time the setting was applied. If you use a zone not shown below, also update clock timezone EST -5 0
and clock summer-time
, for example.
- North America, Eastern Time (UTC-5)
- Europe, Central European Time (UTC+1)
- Brazil, Brasília (UTC-3)
- Australia, Sydney (UTC+11)
North America (specifically Eastern Time, UTC-5):
enable configure terminal clock set 09:00:00 1 Jan 2018 clock timezone EST -5 0 clock summer-time EDT recurring 2 Sun Mar 02:00 1 Sun Nov 02:00 ntp server pool.ntp.org prefer ntp update-calendar exit
Europe (specifically Central European Time, UTC+1):
enable configure terminal clock set 09:00:00 1 Jan 2018 clock timezone CET +1 0 clock summer-time CEST recurring last Sun Mar 02:00 last Sun Oct 03:00 ntp server pool.ntp.org prefer ntp update-calendar exit
Brazil (specifically Brasília, UTC-3):
enable configure terminal clock set 09:00:00 1 Jan 2018 clock timezone BRT -3 0 clock summer-time BRST recurring 3 Sunday October 00:00 3 Sunday February 00:00 ntp server pool.ntp.org prefer ntp update-calendar exit
Australia (specifically Sydney, UTC+11):
enable configure terminal clock set 09:00:00 1 Jan 2018 lock timezone AEST +11 0 clock summer-time AEDT recurring 1 Sunday October 02:00 1 Sunday April 03:00 ntp server pool.ntp.org prefer ntp update-calendar
exit
Confirm the NTP settings
To make sure the settings took effect, run the following command: show clock detail
Synchronize with an NTP server
To make sure the unit has synchronized with an NTP server, run the following command: show ntp status
Exit configuration mode and save changes
If you see Clock is synchronized, you're good to go. Lock in your changes so they'll survive a reboot of the router.
# Save active configuration
end write memory # Save the current running configuration to the startup configuration file copy running-config startup-config