Maintenance and peripherals

System maintenance and troubleshooting is a reoccurring task to take care of your system and be able to analyze and solve technical issues. In addition, peripherals¹ sometimes require some tinkering, which supports in the process of learning the details and quirks of your system. For this reason, the sections in this guide focus on the following tasks:

1. General #Maintenance tasks and automation
2. Setting up #Peripherals
   1. #Bluetooth controller
   2. #Printer and scanner
   3. Additional encrypted #Storage

Maintenance

Ensure the intended system functionality over a period of time: constantly check for errors by using the following command to identify failed systemd services:

sudo systemctl --failed

Use the Systemd journal to read logfiles as follows:

sudo journalctl -p 3 -b

Xorg troubleshooting also starts by checking the Systemd journal. Its own logfiles are created in case of any errors inside your user directory. The filename scheme is in the form of Xorg.n.log with n designating the display number. Search your user directory for such files by using this command:

grep -e Log -e tty Xorg.0.log

Search the forumsand ask questions, lookup terms in the ArchWiki, and consult a search engine of your choice for debugging errors and interpreting warnings.

Examples

The following examples are some issues that I encountered.

A failed service

In my case pkgfile-update.service fails due to missing internet connectivity. This is a typical situation on a notebook with no constant internet connection. A solution is to adapt the service unit by using a drop-in file to run the service after nss-lookup.target is reached.

The drop-in file is created using the command:

sudo systemctl edit pkgfile-update.service --drop-in=nss-lookup.conf

And its content is:

[Unit]
After=nss-lookup.target

To force a re-run of the service use:

sudo systemctl --now start pkgfile-update.service

sudo pacman -Rns pkgfile

sudo rm -rf /var/cache/pkgfile

Backup

Most important is to maintain a backup² of your system. Filesystem level backup can be done via rsync and disk cloning is a task for the ddrescue copmmand. It supports block devices including (optical) disks and SD cards. Install the following packages:

sudo pacman -S ddrescue rsync

Full system backup from $SRC to $DST excluding directory contents of devices and typical mount points is achieved using this command:

sudo rsync -aAXv --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found"} $SRC/ $DST/

Note that the trailing slash is mandatory for synchronizing the folder contents! You probably want to write a backup script for automation. I like to backup my the filesystems of my machines into a directory named after the hostname on a physical HDD³ and clean the filesystem in advance to save space:

#!/bin/bash
#
# Full system backup using rsync with deletion of non-existent files in $DST
# https://wiki.archlinux.org/title/Rsync#Full_system_backup

SRC=/
HST=$(hostnamectl hostname)
DST=$(pwd)/$HST

# Remove old local packages to save space
sudo pacman -Scc

# Clean user data cache
rm -rf ~/.cache/*

# Synchronize
sudo rsync \
  -aAXHv \
  --delete \
  --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found"} \
  $SRC \
  $DST

Logfile limit

I like to keep Systemd’s journal size limit below 200 MB. For this setting, I uncomment and adapt a line in the /etc/systemd/journald.conf file to match:

SystemMaxUse=200M

Afterwards I need to restart the Journald service:

sudo systemctl restart systemd-journald.service

Filesystem cleanup

Files which are not owned by any package can be listed and written to a text file with lostfiles. Additionally, the rmlint tool finds (and optionally removes) duplicate files. I install both packages as follows:

sudo pacman -S lostfiles rmlint

Lostfiles command is executed via #sudo:

sudo lostfiles > ~/lostfiles.txt

And in addition, The following command finds broken symlinks⁴ and writes them into another .txt file for easier post-processing:

sudo find / -xtype l -print | sudo tee broken_symlinks.txt

Additionally, I ocasionally create a list of installed packages to investigate potentionally unused or legacy applications by invoking the following command:

sudo pacman -Qqe | sudo tee /etc/pkglist.txt

If you are curious which package occupies how much disk space (and you may decide to remove it), you can run this command to scroll through a list using the less pager⁵:

pacman -Qi | grep -E '^(Name|Installed)' | cut -f2 -d':' | paste - - | column -t | sort -nrk 2 | grep MiB | less

pacman -Qi | grep -E '^(Name|Installationsgröße)' | cut -f2 -d':' | paste - - | column -t | sort -nrk 2 | grep MiB | less

Automation

You may want to automate some of the aforementioned tasks to happen on a regular basis.

Job scheduler

The cronie package is a cron functionality provider on a per-user crontab file and can be installed using:

sudo pacman -S cronie

Package update notifier

I use Kalu as a notifier for package updates available in the official repositories and the AUR. It can be installed with:

yay kalu

I execute kalu & to start the notifier. Though I still need to manually run the upgrade process, Kalu can regularly check new packages and offers a 1-click system upgrade.

Peripherals

Bluetooth

sudo rfkill

There is an increasing amount of peripherals for short-range wireless connection via bluetooth. The basic bluetooth capabilities are provided by bluez and bluez-utils. These packages are installed as follows:

sudo pacman -S bluez bluez-utils

Afterwards I enable and start bluetooth.service:

sudo systemctl enable bluetooth.service
sudo systemctl start bluetooth.service

Follow pairing instructions in the ArchWiki to setup bluetooth devices.

Headset

Connecting a headset via PipeWire, as configured in #Sound system, requires the pipewire-pulse package. Proceed with the section Configuration via CLI similar to pairing other bluetooth devices. Or to ease this process, a full- featured management GUI is Blueman. I install the package via:

sudo pacman -S blueman

Start the application by invoking blueman-applet & and configure bluetooth devices according to the usage documentation.

Known bugs

If the controller is not available or bluetooth seems to crash regularly, disable USB autosuspend to prevent reloading of the btusb module. Create a /etc/modprobe.d/btusb.conf file with the following content to achieve this behavior:

options btusb enable_autosuspend=n

Printer and scanner

CUPS

Printing is realized with CUPS. After installing the package cups:

sudo pacman -S cups

I start and enable its service:

sudo systemctl enable cups.service
sudo systemctl start cups.service

Any further configuration of printers can be done graphically via the web interface available at http://localhost:631. One exception is setting the default paper size. However, appending it to the file /etc/papersize solves this issue due to CUPS’s support lipaper. In Germany the ISO 216 (DIN A4) paper size defines the standard. To set a4 for lipaper I execute the following command:

sudo echo "a4" | sudo tee -a /etc/papersize

SANE

For scanning, I install the sane package to use the SANE library. As a graphical frontend XSane provides vast functionality. I install both packages by executing:

sudo pacman -S sane xsane

Storage

Additional removable storage such as an USB flash drive⁶ or an external HDD/ SSD may be necessary for archiving data at rest. While I tend to use data at rest encryption such filesystems can be mounted automatically by using a key stored in and read from the root filesystem for convenience.

sudo fdisk -l

sudo cryptsetup luksFormat /dev/sda
sudo cryptsetup open /dev/sda csd

df | grep -w '/'

sudo mkfs.ext4 /dev/mapper/csd

sudo tune2fs -m 0 /dev/mapper/csd
sudo e2label /dev/mapper/csd csd
sudo cryptsetup close csd

sudo mkdir /etc/cryptsetup-keys.d
sudo dd if=/dev/urandom of=/etc/cryptsetup-keys.d/csd.key bs=512 skip=4 count=8
sudo cryptsetup luksAddKey /dev/sda /etc/cryptsetup-keys.d/csd.key --key-slot 1

DevUuid=$(sudo blkid | grep /dev/sda | cut --delimiter=' ' --field=2 | sed 's/[^a-z0-9\\-]//g')
echo "csd UUID=$DevUuid /etc/cryptsetup-keys.d/csd.key noauto" | sudo tee -a /etc/crypttab

sudo systemctl daemon-reload

Proceed with the configuration of basic multimedia and web capabilities or go back to the overview and follow instructions for specific use cases.