H2O(8)

💅 H2O 💅

okay bestie, we're doing the H2O manual page, from the System Manager's Manual, section 8 (that's the admin/system commands girlies). pull up a chair, grab a strawberry 🍓, and let's get into it.

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✨ NAME ✨

h2o — the optimized HTTP/1.x, HTTP/2 server 👑

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🌈 SYNOPSIS 🌈

h2o [options]

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🦋 DESCRIPTION 🦋

so H2O is a performance-optimized HTTP/1.x and HTTP/2 web server. and not like, "we bolted HTTP/2 on at the end" — no ma'am, it was designed from the ground up, and it takes full advantage of HTTP/2's features, including prioritized content serving and server push. it's giving main character energy fr fr ✨

this manual page describes the options that the h2o command supports. iykyk.

🫶 real talk though: H2O should in most cases be run as a system service — through a systemd(1) service or an initscript. that's the vibe. that's the move. don't be out here rawdogging it in a terminal unless you know what you're doing.

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🎀 OPTIONS 🎀

• -c, --conf FILE — the configuration file. lowkey important. (default: /etc/h2o/h2o.conf)
• -m, --mode mode — okay so mode is one of these four, and they are NOT the same, bestie, pay attention:
  • worker — the h2o process stays in the foreground and handles all the incoming connections itself. this is the default, no cap.
  • master — h2o gets started using the /usr/share/h2o/start_server helper. in this mode, the start_server process stays in the foreground and spawns an h2o worker process to handle incoming connections. and here's the slay part: you can send SIGHUP to the master process to reconfigure or upgrade the server without service downtime. iconic. no downtime era. 💅
  • daemon — spawns a master process in the background and then exits. ⚠️ heads up: error-log must be configured when you use this mode, because all errors get logged to the error log instead of being output to standard error. so if you forget it, you're just out here with no idea what's happening. tragic.
  • test — tests the configuration and exits. the vibe check mode. 🧚
• -t, --test — a synonym of --mode=test. same energy, shorter to type.
• -v, --version — prints the version number. ⭐
• -h, --help — prints usage help. your friend when you're lost. 🙈

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👑 SEE ALSO 👑

the full documentation for h2o is available in the h2o-doc package, under /usr/share/doc/h2o. go read it, bestie, it's right there.

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🌸 AUTHOR 🌸

H2O was written by DeNa Co., Ltd. and Kazuho Oku, and it's distributed under the MIT license. 💜

this manpage was written by Apollon Oikonomopoulos <apoikos@debian.org> for the Debian project, but may be used by others. shoutout to them, fr fr. 🫶

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and that's the whole page, babes 💖 this was h2o version 2.2.2, dated September 2017, section H2O(8) — love that for us. go forth and serve some HTTP/2. periodt. 🌈✨