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diff --git a/einhyrningsins.1.html b/einhyrningsins.1.html new file mode 100644 index 0000000..10f54ff --- /dev/null +++ b/einhyrningsins.1.html @@ -0,0 +1,190 @@ +<!DOCTYPE html> +<html> +<head> + <meta http-equiv='content-type' value='text/html;charset=utf8'> + <meta name='generator' value='Ronn/v0.7.3 (http://github.com/rtomayko/ronn/tree/0.7.3)'> + <title>einhyrningsins(1) - graceful restarts for socket-based daemons</title> + <style type='text/css' media='all'> + /* style: man */ + body#manpage {margin:0} + .mp {max-width:100ex;padding:0 9ex 1ex 4ex} + .mp p,.mp pre,.mp ul,.mp ol,.mp dl {margin:0 0 20px 0} + .mp h2 {margin:10px 0 0 0} + .mp > p,.mp > pre,.mp > ul,.mp > ol,.mp > dl {margin-left:8ex} + .mp h3 {margin:0 0 0 4ex} + .mp dt {margin:0;clear:left} + .mp dt.flush {float:left;width:8ex} + .mp dd {margin:0 0 0 9ex} + .mp h1,.mp h2,.mp h3,.mp h4 {clear:left} + .mp pre {margin-bottom:20px} + .mp pre+h2,.mp pre+h3 {margin-top:22px} + .mp h2+pre,.mp h3+pre {margin-top:5px} + .mp img {display:block;margin:auto} + .mp h1.man-title {display:none} + .mp,.mp code,.mp pre,.mp tt,.mp kbd,.mp samp,.mp h3,.mp h4 {font-family:monospace;font-size:14px;line-height:1.42857142857143} + .mp h2 {font-size:16px;line-height:1.25} + .mp h1 {font-size:20px;line-height:2} + .mp {text-align:justify;background:#fff} + .mp,.mp code,.mp pre,.mp pre code,.mp tt,.mp kbd,.mp samp {color:#131211} + .mp h1,.mp h2,.mp h3,.mp h4 {color:#030201} + .mp u {text-decoration:underline} + .mp code,.mp strong,.mp b {font-weight:bold;color:#131211} + .mp em,.mp var {font-style:italic;color:#232221;text-decoration:none} + .mp a,.mp a:link,.mp a:hover,.mp a code,.mp a pre,.mp a tt,.mp a kbd,.mp a samp {color:#0000ff} + .mp b.man-ref {font-weight:normal;color:#434241} + .mp pre {padding:0 4ex} + .mp pre code {font-weight:normal;color:#434241} + .mp h2+pre,h3+pre {padding-left:0} + ol.man-decor,ol.man-decor li {margin:3px 0 10px 0;padding:0;float:left;width:33%;list-style-type:none;text-transform:uppercase;color:#999;letter-spacing:1px} + ol.man-decor {width:100%} + ol.man-decor li.tl {text-align:left} + ol.man-decor li.tc {text-align:center;letter-spacing:4px} + ol.man-decor li.tr {text-align:right;float:right} + </style> + <style type='text/css' media='all'> + /* style: toc */ + .man-navigation {display:block !important;position:fixed;top:0;left:113ex;height:100%;width:100%;padding:48px 0 0 0;border-left:1px solid #dbdbdb;background:#eee} + .man-navigation a,.man-navigation a:hover,.man-navigation a:link,.man-navigation a:visited {display:block;margin:0;padding:5px 2px 5px 30px;color:#999;text-decoration:none} + .man-navigation a:hover {color:#111;text-decoration:underline} + </style> +</head> +<!-- + The following styles are deprecated and will be removed at some point: + div#man, div#man ol.man, div#man ol.head, div#man ol.man. + + The .man-page, .man-decor, .man-head, .man-foot, .man-title, and + .man-navigation should be used instead. +--> +<body id='manpage'> + <div class='mp' id='man'> + + <div class='man-navigation' style='display:none'> + <a href="#NAME">NAME</a> + <a href="#SYNOPSIS">SYNOPSIS</a> + <a href="#DESCRIPTION">DESCRIPTION</a> + <a href="#CHILD-API">CHILD API</a> + <a href="#HISTORY">HISTORY</a> + <a href="#STATUS">STATUS</a> + <a href="#COPYRIGHT">COPYRIGHT</a> + <a href="#SEE-ALSO">SEE ALSO</a> + </div> + + <ol class='man-decor man-head man head'> + <li class='tl'>einhyrningsins(1)</li> + <li class='tc'></li> + <li class='tr'>einhyrningsins(1)</li> + </ol> + + <h2 id="NAME">NAME</h2> +<p class="man-name"> + <code>einhyrningsins</code> - <span class="man-whatis">graceful restarts for socket-based daemons</span> +</p> + +<h2 id="SYNOPSIS">SYNOPSIS</h2> + +<p><code>einhyrningsins</code> [<var>OPTIONS</var>] [--] <var>PROGRAM</var> [<var>PROGRAM_ARGS</var>]</p> + +<h2 id="DESCRIPTION">DESCRIPTION</h2> + +<p><code>Einhyrningsins</code> is a socket multiplexer featuring graceful restarts. It runs +multiple copies of a child program, each of which are passed a shared socket +(or multiple shared sockets) to <span class="man-ref">bind<span class="s">(2)</span></span> to and <span class="man-ref">accept<span class="s">(2)</span></span> connections from. +Graceful, rolling restarts enable updates of the child program with zero +downtime and no dropped connections.</p> + +<p>This program requires special support in the child program to achive the +graceful restarts (aka, exiting only after all connection close) and to be able +to bind to inherited file descriptors (as indicated by environment variables). +Child programs must also be able to run in parallel: for example, each copy +must not try to write to the same output file without some form of locking.</p> + +<ul> +<li><p><code>-n</code>, <code>--number</code> <var>COUNT</var>: +How many child processes to spawn.</p></li> +<li><p><code>-b</code>, <code>--bind</code> <var>ADDR</var>:<var>PORT</var>[,<var>OPT</var>...]: +Socket(s) to bind to. <var>OPT</var> specifies flags to be set on the socket. Options +are <code>n</code> for non-blocking (<code>O_NONBLOCK</code>) and <code>r</code> for re-using addresses +(<code>SO_REUSEADDR</code>). Eg, for both options, could pass <code>-b 127.0.0.1:1234,r,n</code>. +This argument can be repeated.</p></li> +<li><p><code>-4</code>, <code>--ipv4-only</code>: +Only accept IPv4 connections</p></li> +<li><p><code>-6</code>, <code>--ipv6-only</code>: +Only accept IPv6 connections</p></li> +<li><p><code>-h</code>, <code>--help</code>: +Print a help menu</p></li> +<li><p><code>--version</code>: +Print program version</p></li> +<li><p><code>-v</code>, <code>--verbose</code>: +More verbose logging and output</p></li> +<li><p><code>--syslog</code>: +Enables logging via <span class="man-ref">syslog<span class="s">(2)</span></span> (for WARN and above).</p></li> +<li><p><code>-m</code>, <code>--manual</code>: +Enable manual (explicit) acknowledge mode, in which each child program must +connect to the master's control socket and "ACK" within a graceperiod, or it +will be considered unhealthy and get restarted.</p></li> +<li><p><code>--drop-env-var</code> <var>VAR</var>: +Clears the given variable from the child's environment. All other variables +are passed through by default. This argument can be repeated.</p></li> +<li><p><code>-d</code>, <code>--socket-path</code> <var>PATH</var>: +Where to create the control socket (default: <code>/tmp/einhorn.sock</code>).</p></li> +<li><p><code>-r</code>, <code>--retries</code> <var>COUNT</var> +How many times to attempt re-spawning before giving up.</p></li> +</ul> + + +<h2 id="CHILD-API">CHILD API</h2> + +<p><code>Einhyrningsins</code> creates children by <span class="man-ref">fork<span class="s">(1)</span></span>-ing a new process and +<span class="man-ref">execve<span class="s">(1)</span></span>-ing to run the proces itself. For every socket specified by a <code>-b</code> +flag, a socket is bound in the main <code>einhyrningsins</code> process and then +explicitly flagged to be passed on to the child processes. This means the child +process will already have a valid file descriptor bound to each of the shared +sockets. The file descriptor numbers are passed via the following environment +variables:</p> + +<dl> +<dt><code>EINHORN_FD_COUNT</code></dt><dd>How many sockets have been passed.</dd> +<dt><code>EINHORN_FD_<NUM></code></dt><dd>One evironment for each socket with <var>NUM</var> from 0 to <code>EINHORN_FD_COUNT-1</code>.</dd> +</dl> + + +<p>When <code>einhyrningsins</code> is run in manual mode, each child process should connect +to the control socket (at the UNIX path given by the <code>EINHORN_SOCK_PATH</code> +variable) and <span class="man-ref">write<span class="s">(2)</span></span> a newline-terminated string like the following, +containing the child's PID number:</p> + +<p> <code>{"command":"worker:ack", "pid":<PID>}</code></p> + +<h2 id="HISTORY">HISTORY</h2> + +<p><code>Einhyrningsins</code> is a partially-comparible re-implementation of <a class="man-ref" href="https://github.com/stripe/einhorn">einhorn<span class="s">(1)</span></a> (a +Ruby program) in Rust. Einhorn itself derived from Unicorn.</p> + +<p>The word "Einhyrningsins" is Icelandic for unicorn.</p> + +<h2 id="STATUS">STATUS</h2> + +<p><code>Einhyrningsins</code> is a for-fun hobby project. It is not feature complete, fully +documented, or tested.</p> + +<h2 id="COPYRIGHT">COPYRIGHT</h2> + +<p>Copyright 2016 Bryan Newbold +License GPLv3+: GNU GPL version 3 or later <a href="http://gnu.org/licenses/gpl.html" data-bare-link="true">http://gnu.org/licenses/gpl.html</a>. +This is free software: you are free to change and redistribute it. There is NO +WARRANTY, to the extent permitted by law.</p> + +<h2 id="SEE-ALSO">SEE ALSO</h2> + +<p><a class="man-ref" href="https://github.com/stripe/einhorn">einhorn<span class="s">(1)</span></a>, <a class="man-ref" href="einhyrningsinsctl.1.html">einhyrningsinsctl<span class="s">(1)</span></a>, <span class="man-ref">socket<span class="s">(7)</span></span></p> + + + <ol class='man-decor man-foot man foot'> + <li class='tl'></li> + <li class='tc'>October 2016</li> + <li class='tr'>einhyrningsins(1)</li> + </ol> + + </div> +</body> +</html> |