Documentation

Archived documentation for older major NTP releases is available:

• 4.2.6-series: applicable to NTP version 4.2.6 through 4.2.6p5.
• 4.2.4-series: applicable to NTP version 4.2.4 through 4.2.4p8.
• 4.2.2-series: applicable to NTP version 4.2.2 through 4.2.2p4.
• 4.2.0
• 4.1.2
• 4.1.1
• 4.1.0
• 3-5.93e

• Reference Library: Whitepapers, RFCs, and other technical documents written by Professor David L. Mills, inventor of NTP.
• NTP Wiki: Community-contributed documentation.
• NTP FAQ:Frequently Asked Questions about the NTP protocol and software distribution.
• Public Time Server Lists: Browse or search for a public primary or secondary time server.
• NTP Google group: Includes postings from original Usenet newsgroup going back to June, 1990.