Linux Boot Paramters - Quick View

How to enter boot prompt parameter?

At Grub prompt press 'e' to edit command before booting.

1) Select second line
2) Again, press 'e' to edit selected command
3) Type any of below parameters.

Parameters:

1.Single  

   - To boot the server in single user mode. (Ex . for root passwd recovery )

2.init=/bin/bash or init=/bin/sh or S or 1

   - To boot the kernel in single user mode (Ex . for root passwd recovery )

3.root=/dev/device

   - Mention wich device/disk to be used as the root filesystem while booting

4.panic=SECOND

   - Specify kernel behavior on panic. Bedefault the kernel will not reboot after a panic.


5.maxcpus=number

   - Specify maximum number of processors for SMP kernel use.

6.debug

   - Enabe kernel Debugging.

7.fastboot

   - To skip the file system FSCK option at the time of Boot.

8.selinux [0 or 1]

  - Disable or enable SELinux at boot time (0 - Diasabe , 1- Enable)

9.raid=/dev/mdN

  - This is used to inform the kernel, howto assembly of RAID arrays at boot time.

10.mem=MEMORY_SIZE

  - This is for Specific amount of memory to be used when the kernel is not able to see the whole system memory. or for testing purpose.

11.hdX=noprobe

   - Disabe te hdX hard disk (ex. hdb=noprobe)

12.rw

   - mount root file system as read-only. This is used before run fsck option for File system after boot.

13. ro

   - mount root file system as read-write mode.

14.initrd /boot/initrd.img

    -     initrd is used to provide/load additional modules. The boot process will load the kernel and an initial ramdisk.   

15.raid=noautodetect

   - To suppress RAID array auto detection.