CentOS 6. X system changes the kernel startup order

Note: Use the console terminal to manage the connection server.

Specific operation steps:

1. Open/etc/grub.conf to view the system kernel. The following screenshot shows that the system has multiple cores:

2. Configuration modification steps:

(1) From the screenshot, we can see that there are two kernel versions, 2.6.32-573.18.1.el6.x86_64 and 2.6.32-431.23.3.el6.x86_64 from top to bottom.

(2) In the grub.conf file, the parameter that determines which kernel version to use for boot is default, which is 0 by default (representing boot from the latest kernel, and the kernel version from top to bottom is 0, 1, 2, etc.).

(3) In this example, if you want to choose to boot from the old version of the kernel, that is, the original kernel of the system, change the default value to 1, and then restart the server to boot from the new kernel.