Grub¶
grub2-mkconfig -o /boot/grub2/grub.cfg
awk -F\' '/menuentry / {print $2}' /boot/grub/grub.cfg
grub2-set-default 'CentOS Linux (4.9.0-rc8-amd64) 7 (Core)'
grub2-editenv list
fix: https://www.supergrubdisk.org/category/download/
grub-customizer¶
sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer
boot .iso¶
https://netboot.xyz/docs/booting/grub
apt install grub-imageboot
mkdir /boot/images && cd /boot/images
wget https://boot.netboot.xyz/ipxe/netboot.xyz.iso
update-grub2
boot repair¶
https://sourceforge.net/p/boot-repair-cd/home/Home/ apt install linux-image-* # if vmlinuz & initrd.img missing
ubuntu¶
sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair
Init¶
| Level | Desc |
|---|---|
| 0 | Halt the system. |
| 1 | Single-user mode (for special administration). |
| 2 | Local Multiuser with Networking but without network service (like NFS) |
| 3 | Full Multiuser with Networking |
| 4 | Not Used |
| 5 | Full Multiuser with Networking and X Windows(GUI) |
| 6 | Reboot. |
ls -R -l /etc/rc*
ls -l /usr/lib/systemd # check `systemd` page for more
ls -l /usr/share/upstart # last release 2014; 3 years ago
ls -l /etc/init.d # SysV init
cat /etc/modules-load.d/*
apt install systemd-sysv # make link: /sbin/init -> /lib/systemd/systemd