diff options
Diffstat (limited to 'doc/s6_system.html')
| -rw-r--r-- | doc/s6_system.html | 68 |
1 files changed, 38 insertions, 30 deletions
diff --git a/doc/s6_system.html b/doc/s6_system.html index 10d52d7..a226a27 100644 --- a/doc/s6_system.html +++ b/doc/s6_system.html @@ -24,9 +24,7 @@ the system. </p> -<div id="interface"> -<h2> Interface </h2> -</div> +<h2 id="interface"> Interface </h2> <pre> s6 system <em>subcommand</em> @@ -36,22 +34,16 @@ the system. <li> No subcommand takes any options. </li> </ul> -<div id="subcommands"> -<h2> Subcommands </h2> -</div> +<h2 id="subcommands"> Subcommands </h2> -<div id="help"> -<h3> help </h3> -</div> +<h3 id="help"> help </h3> <p> <tt>s6 system help</tt> prints a short help message summarizing the options and usage of the <tt>s6 system</tt> command. It is not as detailed as this page. </p> -<div id="boot"> -<h3> boot </h3> -</div> +<h3 id="boot"> boot </h3> <h4> Interface </h4> @@ -68,18 +60,40 @@ a state where everything the user wants is running. </li> program hands off duties. <ul> <li> On a system making use of -<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init/a>, -<tt>s6 system boot</tt> should be the sole command defined in the -<tt>/etc/rc.init</tt> script. </li> - <li> On a system using <tt>/etc/inittab</tt>, the first line -of the inittab should be: <tt>::wait:/usr/bin/s6 system boot</tt> </li> +<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init</a>, +<tt>s6 system boot</tt> should be run by the +<tt>/etc/rc.init</tt> script. No other command needs to appear in +that script. </li> + <li> On a system using <tt>/etc/inittab</tt>, you need to add +two lines at the beginning of <tt>/etc/inittab</tt>: + <ul> + <li> The first line should be a command that runs and respawns +<a href="//skarnet.org/software/s6/s6-svscan.html">s6-svscan</a>, +ideally with a catch-all logger. This could be something like +<tt>::respawn:/usr/lib/s6/s6-svscanboot</tt>, with <tt>/usr/lib/s6/s6-svscanboot</tt> +being similar to the script used +<a href="https://gitlab.alpinelinux.org/alpine/aports/-/blob/master/main/s6/s6-svscanboot?ref_type=heads">in +Alpine Linux</a> to start an instance of s6-svscan supervising its own +catch-all logger. </li> + <li> The second line should be <tt>::wait:/usr/bin/s6 system boot</tt>. </li> + <li> For complete safety, there should be a synchronization mechanism so +that the second line never starts before s6-svscan is ready. A quick and (very) dirty +way to synchronize is polling on s6-svscan before running the +command: <tt>::wait:until s6-svscanctl /run/service 2>/dev/null; do :; done && exec /usr/bin/s6 system boot</tt> </li> + </ul> </li> + <li> It is also possible to run a complete s6 ecosystem under systemd, but it is redundant, +so it's unlikely that anyone would want to do it. For the sake of completeness, +the way would be to define two unit files: the first one to launch s6-svscan, as +documented <a href="//skarnet.org/software/s6/s6-svscan-not-1.html">here</a>, +and the second one, specified to run <em>after</em> the first one, to run +the <tt>s6 system boot</tt> command as a one-shot. </li> </ul> </li> </ul> <p> The rest of the subcommands are shutdown subcommands, and they only work if the machine makes use of -<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init/a> and +<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init</a> and s6-frontend has been configured to support it. On a machine that does not boot via s6-linux-init, a shutdown should be executed via the shutdown commands provided by your init system. In order for @@ -90,9 +104,7 @@ following line should appear in <tt>/etc/inittab</tt>: <code>::shutdown:/usr/bin/s6 live stop_everything -E</code> </p> -<div id="reboot"> -<h3> reboot </h3> -</div> +<h3 id="reboot"> reboot </h3> <h4> Interface </h4> @@ -103,13 +115,11 @@ following line should appear in <tt>/etc/inittab</tt>: <ul> <li> <tt>s6 system reboot</tt> reboots the machine. <li> This only works if the machine makes use of -<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init/a> and +<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init</a> and s6-frontend has been configured to support it. </li> </ul> -<div id="poweroff"> -<h3> poweroff </h3> -</div> +<h3 id="poweroff"> poweroff </h3> <h4> Interface </h4> @@ -121,13 +131,11 @@ s6-frontend has been configured to support it. </li> <li> <tt>s6 system poweroff</tt> halts the system and turns the power off. </li> <li> This only works if the machine makes use of -<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init/a> and +<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init</a> and s6-frontend has been configured to support it. </li> </ul> -<div id="halt"> -<h3> halt </h3> -</div> +<h3 id="halt"> halt </h3> <h4> Interface </h4> @@ -139,7 +147,7 @@ s6-frontend has been configured to support it. </li> <li> <tt>s6 system halt</tt> halts the system without turning the power off. </li> <li> This only works if the machine makes use of -<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init/a> and +<a href="//skarnet.org/software/s6-linux-init/">s6-linux-init</a> and s6-frontend has been configured to support it. </li> </ul> |