This is an old revision of the document!
Table of Contents
๐ NTP Configuration on Windows Server 2024
NTP Configuration on Aruba CX 6300 / 6400 (Houston, TX)
To configure the Windows Time Service (w32time
) and synchronize with specific NTP servers, run the following commands as Administrator from PowerShell or CMD.
๐ Example 1 โ Global NTP Pool Servers
w32tm /config /manualpeerlist:"0.pool.ntp.org 1.pool.ntp.org 2.pool.ntp.org 3.pool.ntp.org" /syncfromflags:manual /reliable:yes /update net stop w32time net start w32time w32tm /resync
*Use this option for general-purpose global synchronization.*
โ๏ธ Example 2 โ Google and Cloudflare NTP Servers
w32tm /config /manualpeerlist:"time.google.com time.cloudflare.com" /syncfromflags:manual /reliable:yes /update net stop w32time net start w32time w32tm /resync
*Use this option if you prefer high-availability public NTP providers.*
๐ Verification
After applying the configuration, check synchronization status:
w32tm /query /status w32tm /query /peers
Expected results:
Source
โ should show one of the configured NTP servers.Stratum
โ indicates synchronization level (lower = better).Last Successful Sync Time
โ confirms proper operation.
๐ง Notes
/manualpeerlist
โ Defines NTP servers (internal or external)./syncfromflags:manual
โ Forces use of the listed servers only./reliable:yes
โ Marks this server as a reliable time source (for domain controllers)./update
โ Applies settings immediately./resync
โ Forces an instant synchronization.
๐ NTP Configuration on Aruba CX 6400 (Houston, TX)
To configure the switch to synchronize its time using public NTP servers and apply the correct time zone for Houston (Central Time), run the following commands in configuration mode:
configure terminal ! Configure DNS servers for name resolution (required for NTP hostnames) ip dns server-address 8.8.8.8 ip dns server-address 1.1.1.1 ! Configure public NTP servers (requires DNS resolution) ntp server 0.pool.ntp.org ntp server 1.pool.ntp.org ntp server 2.pool.ntp.org ntp server 3.pool.ntp.org ! Enable NTP service ntp enable ! Set time zone to Central Time (Houston, TX) clock timezone america/chicago exit write memory
๐ Verification
Check synchronization and clock status:
show ntp associations show ntp status show clock
Expected output:
show ntp associations
โ an asterisk (*) indicates the currently synchronized NTP source.show clock
โ displays local time adjusted to Central Time (CST/CDT).show ntp status
โ should reportsynchronized
after a few minutes.
๐ง Notes
- DNS servers (
dns server
) are mandatory if you use hostnames (e.g.pool.ntp.org
); otherwise, specify NTP servers by IP. america/chicago
automatically handles daylight saving time.- If using an internal NTP source (e.g. Windows Server), replace pool servers with its IP (e.g.
ntp server 10.28.64.22
). - NTP uses UDP port 123 โ ensure it is allowed for outbound traffic.
- Save configuration permanently with
write memory
.
๐ NTP Configuration on Aruba 2930M (Houston, TX)
This configuration allows the Aruba 2930M switch (AOS-Switch) to keep accurate time using public NTP IP servers and the correct Central Time zone.
configure terminal # Configure DNS servers (only if not already defined) no ip dns server-address priority 1 no ip dns server-address priority 2 ip dns server-address priority 1 8.8.8.8 ip dns server-address priority 2 1.1.1.1 # Configure public NTP servers (IP addresses only) ntp server 216.239.35.0 ntp server 162.159.200.1 ntp server 129.6.15.28 ntp server 132.163.96.5 # Set time zone to Central Time (Houston, TX) time timezone -360 # Enable Daylight Saving Time for USA time daylight-time-rule continental-us-and-canada exit write memory
๐ Verification
Run the following commands to verify time synchronization:
show ntp status
show time
show clock
Expected output:
System time synchronized to NTP Server
โ indicates active NTP source.Time zone offset: -360
โ confirms Central Time (UTCโ6).Daylight time rule: USA
โ daylight saving enabled.
๐ง Notes
- The 2930M does not support NTP hostnames โ only IP addresses.
- If you have a local NTP server (e.g., Windows at 10.28.64.22), replace the public IPs with:
ntp server 10.28.64.22
- Use
show ip dns
to confirm DNS configuration. - Save configuration permanently with
write memory
.