How to fix Linux can not start failure

Summary: No operating system ensures 100% reliability. One day, even Linux will not start. This article gives you some strategies for using Linux workstations that do not start properly.

No operating system ensures 100% reliability. One day, even Linux will not start. This article gives you some strategies for using Linux workstations that do not start properly.

No matter how much you love your Linux machine, sometimes you have to restore your system. Yes, even a Linux machine can suffer a system crash: this is inevitable whether it is due to a video configuration error, a kernel update error, or an init script configuration error. I have seen a lot of this —— even on my own machine, most of it is due to X configuration error —— this is really frustrating.

Using the correct runlevel

After installing a new Linux system, I immediately took steps to ensure that the disaster does not happen easily. One of the measures is to edit the operating level of the system. The run level tells the system how far it is from taking the boot process. The running level is divided into six levels:

Level 0: Stop (do not set initdefault)

Level 1: Single User Mode

Level 2: Multi-user mode, no NFS (Same as level 3, if you don't have a network)

Level 3: Complete multi-user mode

Level 4: Not used

Level 5: X11

Level 6: Restart (do not set initdefault)

The new Linux system almost always uses Run Level 5 (X11) by default, indicating that the system will stop at the graphical login interface after the boot is complete. . The system works fine before something (or someone) uses the X configuration.

Then you have to find a login method. You can press [Ctrl][Alt][F7] to enter a text-based virtual window, but why bother? Instead, I always change the runlevel to level 3 in the /etc/inittab file. The code you changed is:

id:5:initdefault:

It is changed to:

id:3:initdefault:

When X is wrong This is a very simple method of system recovery.

Multi-Core

Another obvious method of disk recovery is to always install a working kernel. I usually work on a kernel that is updated via yum. Sometimes, the kernel will have some errors that prevent one or more of my machines from starting.

To avoid this, I always promise to use at least one functioning kernel on my machine. To solve this problem, first add plugins=1 to the /etc/yum.conf file, then apply the script and name it n-installonly.py, which is saved in the /usr/lib/yum-plugins file. . You can update the number of cores used by the system by modifying the tookeep variable (default is 2).

Knowing that there is a working kernel on the system, you can perform a security upgrade. If the new kernel fails, simply boot the old kernel to resolve the problem on the new kernel (whether it is deleted, recompiled, or upgraded).