| |
CentOS 6.x installation process that many people feel can be installed, no need to understand is how to install, but I have eaten this before due to the loss (interview), they still write it down, in case we met, you can there is a reference.
We first look at the CentOS installation CD in the directory:
We explain the role of these directories (file no role, are some KEY file, GPL information, etc.)
About EFI EFI # files using Boot
images # installation image install.img and something about pxe boot files
isolinux # boot file directories, including vmlinuz, initrd.img, isolinux.bin etc.
Packages # rpm package common
repodata #yum index source, and some documentation
Our main concern here images and isolinux directory, just as in the catalog EFI EFI boot so I can not get to the bottom, the other two directories are also added.
1.images contents of the directory:
pxeboot catalog:
install.img files, mirroring the installer is located, the system is installed by this image of the anaconda installation program.
vmlinuz is the compressed kernel, the boot program starts first thing in the kernel boot;
initrd.img is for kernel provides some additional drivers and a file system simulation environment.
efi efi boot still on, ignore it.
2.isolinux catalog:
The more the file directory, we only need to be concerned about the following few:
isolinux.bin # boot program (can be understood as bootloader), the program will start after the BIOS POST
isolinux.cfg # bootloader configuration file
vmlinuz # compressed kernel, isolinux.bin will start after starting vmlinuz and initrd.img
initrd.img # provide drivers and the kernel provides basic system environment, which is a small file system, for which there is a kernel calls init program used to start anaconda
grub.conf # grub provided sample configuration files, the installation does not start grub so less than
We found, pxeboot and isolinux directories all contain vmlinuz and initrd.img, these two files in the directory are actually identical.
Repeated blows, we really need to care about the fact that only a few below:
1.isolinux.bin
2.isolinux.cfg
3.vmlinuz
4.initrd.img
5.install.img
The installation process is roughly like this:
After inserting the disc and turn on the computer will self-test (POST), the self-test no problem, it will start BIOS, BIOS boot order to find the CD and find BOOTLoader according to, at this time BOOTLoader is isolinux.bin, isolinux.bin according isolinux .cfg provides a menu interface (vesamenu.c32 start the program) allows the user to select the operation, look at the file isolinux.cfg
default vesamenu.c32 # program provides a menu function, if not in interactive mode, then you can skip
#prompt 1 # whether to enter the interactive mode, 1, 0 N
timeout 600 # timeout period
display boot.msg # show boot.msg file, futile, can be ignored
menu background splash.jpg # This displays a background paper, isolinux directory can be seen splash.jpg
menu title Welcome to CentOS 6.5! # play a Welcome to CentOS 6.5!
menu color border 0 #ffffffff # 00000000
menu color sel 7 #ffffffff # ff000000
menu color title 0 #ffffffff # 00000000
menu color tabmsg 0 #ffffffff # 00000000
menu color unsel 0 #ffffffff # 00000000
menu color hotsel 0 # ff000000 #ffffffff
menu color hotkey 7 #ffffffff # ff000000
menu color scrollbar 0 #ffffffff # 00000000 These are color profile
label linux # This is the start tag
menu label ^ Install or upgrade an existing system # installation or upgrade system
menu default # default startup label
kernel vmlinuz # boot kernel
append initrd = initrd.img # start initrd
label vesa
menu label Install system with ^ basic video driver # install basic equipment
kernel vmlinuz # boot kernel
append initrd = initrd.img xdriver = vesa nomodeset # boot initrd and install basic equipment parameters
label rescue
menu label ^ Rescue installed system # rescue mode
kernel vmlinuz
append initrd = initrd.img rescue # started rescue mode
label local
menu label Boot from ^ local drive
localboot 0xffff
label memtest86
menu label ^ Memory test
kernel memtest
append -
We can see, in fact, isolinux.bin read isolinux.cfg file and starts vesamenu.c32, the background image is loaded, then the option menu. After the user selects the installation menu, isolinux according to the information (we are here first):
label linux # is the start tag
menu label ^ Install or upgrade an existing system # installation or upgrade system
menu default # default startup label
kernel vmlinuz # boot kernel
append initrd = initrd.img # start initrd
Boot kernel and initrd (initrd can append parameters), and tells the kernel to perform the installation. initrd role is to become a basic virtual file system, which contains a number of commands and drivers, and so, according to the initrd kernel find install.img program, install.img start anaconda program interacts with the user to complete the installation of the operating system (anaconda can Depending on the configuration files automatically install the system, you need to provide a kickstart file). |
|
|
|