tailieunhanh - Bài giảng Quản trị Linux: Service and boot loader management - Đặng Thanh Bình

Bài giảng Quản trị Linux: Service and boot loader management. nội dung chính trong chương này gồm có: Boot sequence, runlevels, bootloader configurationm, what is the “init system”? System V, upstart, systemd. . | Đặng Thanh Bình Service and Boot Loader Management Contents • • • • • • • Boot sequence Runlevels Bootloader configuration What is the “init system”? System V Upstart systemd BOOT SEQUENCE Boot phases • BIOS performs integrity checks on memory and seeks instructions on the Master Boor Record (MBR). • The MBR points to the boot loader (GRUB or LILO). • Boot loader – asks for the OS label which will identify which kernel to run and where it is located (hard drive and partition specified). – loads the Linux operating system. • The kernel executes init program (SysV/Upstart/Systemd) Boot phases • SysV – The first processes that init starts is a script /etc/ – Based on the appropriate run-level, scripts are executed to start various processes to run the system and make it functional. • Upstart: Some core boot tasks started by upstart are – Plymouth - The graphical boot animation and logger – mountall - Mounts all filesystems defined on /etc/fstab – network* - Network related services – Display Manager .