We can now attempt to go through each stage of the booting process.
If the bootloader is successful it will start its second stage which displays a prompt or a splash image with a list of operating systems or kernels to boot
If an initial ram disk is specified it is loaded here.
The kernel is loaded into memory
The kernel is loaded from the medium, specified in the
lilo.conf or grub.conf
configuration file. As it loads it is decompressed. If
an initial ramdisk is loaded, extra modules are loaded here
The kernel will scan the hardware in the system: CPU, RAM, PCI bus, etc
The kernel then mounts the root device as read-only
From here on programs in /bin and
/sbin are made available.
The kernel then loads /sbin/init - the first 'userspace' process.
init reads /etc/inittab
and follows the instructions.
the default runlevel is read
the rc.sysinit is run
all local filesystems are mounted or, if needed, an integrity check (fsck) is performed in accordance with entries in
/etc/fstabthe current kernel logs are dumped to a file
dmesg > /var/log/dmesg
quotas are started, etc ...
the kernel and system logger service is started. The system log file is
/var/log/messages
next init goes into the default runlevel /etc/rc.d/rc
Nthe gettys start and the boot process is over
![[Note]](images/note.png) | /var/log/dmesg and /var/log/messages |
|---|---|
Make sure you have noted the difference between these two files from the description above |
The prompt to login is now managed by the gettys on the ttys. After the user has typed in their username and pressed return /bin/login is started.
The user is prompted by /bin/login for the password. The user enters a password and presses return.
The password entered by the user is compared to the password in
/etc/passwd or /etc/shadow.
