5. boot process

5. boot process

• 1.
  5 – Bootprocess Marian Marinov Borislav Varadinov CEO of 1H Ltd. System Administrator mm@1h.com bobi [ at ] itp.bg
• 2.
  ● Local boot process – HDD – CD – USB ● Boot loaders ● Remote booting – With local drives – Without local drives
• 3.
  ➢ Hardware initialization ➢ Find all storage controllers ➢ Initialize all storage controllers ➢ BIOS storage search ➢ Depending on the BIOS boot priority list ➢ Hard Disks ➢ CD ➢ USB ➢ Floppy ➢ Network
• 4.
  ● Identify bootable device ● Search for boot loader ● Copy the loader into memory
• 5.
  ➢ Search thefirst 1024 bytes ➢ If partition table is found, search for the first PRIMARY partition marked as BOOT ➢ Search the first 1024 bytes of the partition ➢ Load the boot loader into memory ➢ Set the Instruction Pointer to the beginning of the boot loader binary
• 6.
  Boot loaders ➢ LILO ➢ GRUB/GRUB2 ➢ SYS/ISOLINUX ➢ uBoot ➢ PXElinux
• 7.
  Boot loaders ➢ LILO ➢ Direct block offset to the kernel ➢ The loader and its configuration is written directly in the MBR ➢ Support for serial console ➢ Kernel parameters prompt /etc/lilo.conf image = /boot/bzImage-3.8.2-terion root = /dev/sdb2 label = Terion-3.8.2 read-only
• 8.
  Boot loaders ➢ GRUB/GRUB2 ➢ Only the base loader data is written in the MBR, everything else is read from the device ➢ Dynamic configuration ➢ Shell like command prompt ➢ Support for serial console ➢ Support network loading of binaries
• 9.
  Boot loaders ➢ GRUB /boot/grub/menu.lst titleCentOS (2.6.32-279.14.1.el6.x86_64) root (hd0,1) kernel /vmlinuz-2.6.32-279.14.1.el6.x86_64 ro root=/dev/sda4 crashkernel=auto SYSFONT=latarcyrheb-sun16 LANG=en_US.UTF-8 KEYTABLE=us initrd /initramfs-2.6.32-279.14.1.el6.x86_64.img
• 10.
  Boot loaders ➢ GRUB2 menuentry'Fedora (3.7.6-201.fc18.i686)' --class fedora --class gnu-linux --class gnu --class os { load_video set gfxpayload=keep insmod gzio insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set=root f098d5f7-abf7-4161-966b- b265c6179abe echo 'Loading Fedora (3.7.6-201.fc18.i686)' linux /vmlinuz-3.7.6-201.fc18.i686 root=UUID=c567e7ef-eb7e-4ced-8c21- 64d1075eb72e ro rd.md=0 rd.lvm=0 rd.dm=0 KEYTABLE=us quiet SYSFONT=latarcyrheb-sun16 rhgb rd.luks=0 LANG=en_US.UTF-8 echo 'Loading initial ramdisk ...' initrd /initramfs-3.7.6-201.fc18.i686.img }
• 11.
  Boot loaders ➢ ISO/SYSLINUX ➢ Mainly used for live/install CD/USB ➢ Static configuration ➢ No command prompt
• 12.
  Boot loaders ➢ uBoot ➢ Developed entirely for embedded devices ➢ EVERYTHING embedded runs this ➢ Configuration similar to SYSLINUX
• 13.
  Network Boot ➢ Optional(boot)ROM ➢ Currently implemented directly in the BIOS on almost all new hardware ➢ With local storage ➢ Without local storage
• 14.
  Network Boot BIOS DHCP Server Acquire IP address Load Network boot loader Optional ROM TFTP Server Boot loader Load OS Kernel Kernel
• 15.
  Boot process http://academy.telerik.com/student-courses/software-technologies/os-windows-linux/
• 16.
  Beer time
• 17.
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