diff --git a/Linux/systemd.md b/Linux/systemd.md index 6bb1b47..5ffbc49 100644 --- a/Linux/systemd.md +++ b/Linux/systemd.md @@ -4,7 +4,7 @@ categories: tags: [systems-programming] --- -# `systemd` +# systemd Once the [boot process](/Operating_Systems/Boot_process.md) has completed and the bootloader has located the kernel and injected it into memory the first user space program runs: `init` (for _initialisation_). `init` is a [daemon](/Operating_Systems/Daemons.md) process that continues running until shutdown and is responsible for starting all the processes that are prerequisites for user space. For example: network connections, disk access, user logins etc. @@ -16,7 +16,7 @@ On Linux systems `systemd` is used to implement `init`. > `systemd` can track individual service daemons after they start, and group together multiple processes associated with a service, giving you more power and insight into exactly what is running on the system _How Linux Works: Third Edition_, Brian Ward 2021 -## How `systemd` works +## How systemd works ### Goal-directed units @@ -41,7 +41,7 @@ Units are organised into **unit types**. The main types that run at boot time ar For example, at boot, a target unit called `default.target` groups together a number of service and mount units as dependencies. These then run in a graph-like dependency structure where a unit that comes late in the boot process can depend on several previous units making earlier branches of a dependency tree join back together. -## `systemd` configuration files +## systemd configuration files Units are managed via `systemd` configuration files. @@ -92,7 +92,7 @@ Also=uuidd.socket - `Service` constitutes the main specification for the unit - `Install` is the call to set the dependencies running before the `Service` functions are accessible. -## `systemd` operations: `systemctl` +## systemd operations: systemctl The `systemctl` command is the chief way of interacting with `systemd`. You use it to activate and deactivate services, list their status, reload the configuration and so. @@ -188,6 +188,6 @@ systemctl disable mongodb.service Removed "/etc/systemd/system/multi-user.target.wants/mongodb.service". ``` -## Why use `systemd` over `cron` ? +## Why use systemd over cron ? https://mark.stosberg.com/2016-08-26-rsnapshot-and-systemd/