ntp を Homebrew でインストール

プロジェクトリンク

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コマンドとエイリアス

• ntp-keygen
• ntp-wait
• ntpd
• ntpdate
• ntpdc
• ntpq
• ntptime
• ntptrace
• sntp
• update-leap

プロジェクトの歴史

NTP predates most packages in this database. The NTP FAQ says the first NTP implementation started around 1980, after earlier Internet clock-service work, and that the name Network Time Protocol first appeared in RFC 958 in September 1985. David L. Mills authored RFC 958.

The FAQ traces the protocol through RFC 1059 for NTP version 1 in 1988, RFC 1119 for version 2 with symmetric-key authentication, RFC 1305 for version 3 in 1992, and later NTPv4 work. It also notes that `xntp`, written by Dennis Fergusson at the University of Toronto, evolved into the public software distribution.

採用の歴史

NTP became foundational Internet infrastructure because clocks affect logs, authentication, distributed systems, filesystems, Kerberos, TLS validation, monitoring, and incident response. The package is less a trendy CLI than a long-lived system service that operating systems either ship directly or replace with compatible descendants such as chrony, systemd-timesyncd, OpenNTPD, or NTPsec.

The Homebrew package remains useful for admins who specifically need the reference-style tools such as `ntpd`, `ntpq`, `ntpdate`, `sntp`, and `ntptime` on macOS or in reproducible package environments.

使われ方

Package users configure servers and peers in `/etc/ntp.conf`, run `ntpd` as a daemon, inspect associations with `ntpq`, generate or manage keys with `ntp-keygen`, perform one-shot synchronization with `ntpdate` or `sntp`, and maintain leap-second data with `update-leap`.

The practical split is operational: small systems often only need client synchronization, while infrastructure operators care about strata, upstream server selection, authentication, drift behavior, and monitoring offset/jitter over time.

パッケージ好きにとっての重要性

NTP is package history as infrastructure history. It is one of the quiet protocols that made distributed computing less chaotic, and the brew formula packages the traditional toolchain rather than a newer reimplementation.

タイムライン

• Around 1980: first NTP implementation, per the NTP FAQ.
• 1985-09: RFC 958, Network Time Protocol, published by David L. Mills.
• 1988: RFC 1059 specified NTP version 1.
• 1989: RFC 1119 specified NTP version 2.
• 1992: RFC 1305 specified NTP version 3.
• 2010-06: RFC 5905 specified NTP version 4.

Related projects

• xntp
• NTPsec
• OpenNTPD
• chrony
• systemd-timesyncd

ソース

• https://formulae.brew.sh/formula/ntp
• https://www.ntp.org/ntpfaq/NTP-s-def-hist/
• https://www.rfc-editor.org/info/rfc1059
• https://www.rfc-editor.org/info/rfc1119
• https://www.rfc-editor.org/info/rfc1305
• https://www.rfc-editor.org/info/rfc5905
• https://www.rfc-editor.org/info/rfc958