feat: Add openrc-async-services

content/posts/openrc-async-services.md

@@ -0,0 +1,52 @@
+---
+title: "OpenRC: Start services after login prompt"
+date: 2021-11-17T21:14:15+01:00
+draft: false
+---
+
+I'm using Alpine Linux as my main OS on desktop.
+As I don't use any display manager/greeter such as LightDM's,
+I noticed that it takes quite a bit of time to actually get the login prompt.
+After a while of searching through logs,
+I realized that some services - primarily `chronyd` - wait
+a few seconds for e.g. getting a response from NTP server
+and don't exit the start function immediately after starting the process.
+I tried googling for a solution and found [this](https://unix.stackexchange.com/a/579014)
+Unix StackExchange answer, yet it didn't solve my problem.
+
+_But_, after reading Alpine User Handbook's page on
+[OpenRC](https://docs.alpinelinux.org/user-handbook/0.1a/Working/openrc.html),
+I got the idea that it could be solved with a bit of tinkering with custom runlevels.
+
+So, the final solution was:
+
+- create a custom runlevel (I chose the name "async", but it doesn't matter)
+
+```bash
+sudo mkdir /etc/runlevels/async
+```
+
+- add `default` as a [stacked runlevel](https://wiki.gentoo.org/wiki/OpenRC/Stacked_runlevel)
+
+```bash
+sudo rc-update add -s default async
+```
+
+- remove services from `default` and add them to `async`
+
+```bash
+sudo rc-update del chronyd
+sudo rc-update add chronyd async
+```
+
+- add changing runlevel to `async` to `inittab`
+
+Add this line to `/etc/inittab`:
+
+```
+::once:/sbin/openrc async
+```
+
+After rebooting, services from `default` runlevel will still block agetty
+from running (after all, it has the `wait` label in inittab), but services
+from `async` will start separately.