Linux Admin Land
Group Management
Create Group
groupadd $group_name
User Management
Create User
useradd $user_name -d /home/$user_name -m -N -g $primary_group_name
- -m create home directory
- -N do not create user group with the same name as the user
Fix Installer Invalid or Corrupted Package:
sudo find /var/cache/pacman/pkg/ -iname "*.part" -exec rm {} ;
sudo pacman -SyyuCreate User with UID
useradd -u $user_id -g $group_id -M -s /usr/bin/nologin $user_name
- -M is without home directory
- -u is specific user ID
- -g is specific group ID
- -s change login shell
Change User Schell
chsh $user_name
< /bin/bash
Add Existing User to Existing Group
usermod -a -G $group_name $user_name
systemd
List all service files
systemctl list-unit-files
systemctl list-unit-files | grep name
Reload
Every time .service, .path systemd unit file changes systemctl needs to reload with:
systemctl daemon-reload
To Start on Boot
systemctl enable $name.service
Tail service logs
journalctl -u $unit_name
where $unit_name can be a short name like sshd instead of sshd.service.
Grub
Reinstall
Update grub.cfg after making any changes to /etc/default/grub or any file in /etc/grub.d/:
grub-mkconfig -o /boot/grub/grub.cfg
Install boot loader:
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=GRUB