Boot sequence<\/p>\n
Components in the file grub.conf<\/p>\n
Few parameters in grub.conf kernel:<\/strong> The kernel to be used<\/p>\n Rhgb quiet: <\/strong>This will hide the kernel messages<\/p>\n Initrd:<\/strong> will have image of “necessary” drivers while booting.<\/p>\n If another OS (Windows) is also installed the grub.conf file will have another block with<\/p>\n Grub prompt GRUB> root (hd0, “press tab key” If the \/ is in (hd0,4), we could type “cat \/etc\/groups” to see the contents of the “groups” file.<\/p>\n If grub cannot find the kernel to be used do the following:<\/p>\n Run level:<\/p>\n If the system do not bootup following could be tried:<\/p>\n Init The rc0 will have only kill commands. All the links in rc6 will start with ‘K’ by norm<\/p>\n No 1 – 6 in the inittab runs getty. These are definitions for the virtual terminals. Note: \/etc\/security will have info about the terminals root can log in.<\/p>\n # init -q
\nroot (0,0) :<\/strong> This means the root is in hard disk 1, partition 1<\/p>\n\n
\nAt the booting time, when the menu to choose the OS appears, pressing “c” will bring us the grub prompt (GRUB >).
\nHere various commands could be executed. Example:<\/p>\n
\nThis will show the various partitions<\/p>\n\n
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\nInit -> inittab -> will call for many other files including rc0 to rc6<\/p>\n
\nIf we add a line : “20:2345:respawn:\/sbin\/migetty tty 20” a new terminal will be added. This new terminal will work only after reboot.<\/p>\n
\n# chvt 20 is to switch terminal using CLI.
\nChange run level at bootup\/grub
\nIf we want to switch to a different run level at the bootup itself, the following has to be done at the boot prompt at startup.<\/p>\n\n