Installing and configuring NTP on Ubuntu Server

建議您盡可能不要搭配Compute Engine VM 使用外部NTP 來源。 更糟的情況是，同時使用Google 的NTP 服務與外部服務可能導致系統時間出現無法預測的變更。

Configure your network settings to use time.google.com as your NTP server. Read our configuration instructions and terms of service. We recommend that you ...

Click the Change settings... button. Check the box Synchronize with an Internet time server. Next to Server:, enter time.google.com .

臉書Facebook - NTP Server time1.facebook ... google.com 參考資料: https://developers.google.com/time/. 國家時間與頻率標準實驗室- NTP Server

我剛才在讀網路文章的時候，我才發現，原來Google也有對外服務的NTP伺服器，網址分別有五個： TIME.google.com. TIME1.google.com. TIME2.google.com

While the actual URL for the Google public NTP servers is time.google.com, most servers can't handle a canonical domain name (ie. time.google.com), ...

216.239.35.0 - IP Info. The following page provides details on applications, hostnames, network point-of-presence, and more.

您的Server或工作站、個人電腦安裝後，可使您電腦系統之時刻與國家標準同步在0.02-0.1秒之內（視網路連線狀況而定）。 您可以在http://www.stdtime.gov.tw或http://www.ntp.

Google's turned on a set of public network time protocol (NTP) servers. You'll find the servers at time.google.com – which resolves to 216.239.35.0.

NTP時間伺服器Domain FQDN列表IP List · 1.tw.pool.ntp.org · 2.tw.pool.ntp.org · 3.tw.pool.ntp.org.