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This article shows you the configuration parameters of Ubuntu Grub, the content is concise and easy to understand, absolutely can make you shine, through the detailed introduction of this article I hope you can gain something.

GRUB works in its configuration file mode, and to configure GRUB, you only need to modify/boot/grub/grub.conf or/etc/grub.conf (/etc/grub.conf is a symbolic link to/boot/grub/grub.conf). The GRUB configuration file can actually be divided into two parts, in the beginning of the "#" are comment lines, you can ignore; the other part is the role of the parameters part, the following for everyone to introduce.

Ubuntu Grub configuration parameters default

This parameter determines the boot label on which the cursor departs by default when GRUB boots. If default=0, GRUB boots with the cursor resting on *** boot labels. If you change 0 to 1, GRUB boots with the cursor resting on the second boot label by default.

Ubuntu Grub configuration parameters timeout

This parameter sets the wait time for GRUB. When the computer boots to the boot page, GRUB has a default wait time of 10 seconds, and if the user does not make any selection within the default time, GRUB will automatically boot the system according to the default parameter setting.

Users can also set timeout parameters according to their own needs. If timeout=30, the default wait time for GRUB is set to 30 seconds, and if the timeout parameter is removed or the number after the equal sign is changed to a negative number, this parameter will be invalidated, and GRUB will remain on the boot page waiting for the user to select.

Ubuntu Grub configuration parameters splashimage

When entering the GRUB boot interface, you can see a background image, and the parameter provides this function. To make GRUB boot more personalized, you can also prepare an XPM image yourself, then compress the image into gz format, *** modify the file path in the splashimage parameter. However, if splashimage is removed, GRUB's boot menu will be the same as NT Loader, turning into the most common white text on a black background, which is very ugly.

Ubuntu Grub configuration parameters title

In fact, title is a guide label, we can modify the text part after title to make it more compound our usage habits. If you change the title Red Hat Enterprise Linux AS to the title Red Hat Linux, when you enter the GRUB boot interface again, the boot menu will change to Red Hat Linux. Is it obvious? (Author tip: title The following part is the information required for system guidance, do not modify it!)

Ubuntu Grub configuration parameters password

It is well known that it is easy to enter single-user mode by editing the GRUB boot parameters to change the root password, which undoubtedly increases the security risk for a multi-user computer or server. It must be like adding a lock to your GRUB. You can set the password to GRUB through the password parameter of GRUB.

GRUB password settings can be divided into global passwords and menu passwords.

To prevent others from modifying the root password via GRUB, you need to set a global password. vi /boot/grub/grub.conf Add password= password to the next line of splashimage parameter. After saving, restart the computer. When you log in to the GRUB menu page again, you will find that you can no longer edit the boot label directly using the e command. You must first use the p command and enter the correct password before you can edit the boot label.

Although we set the global password, if someone else gets the global password, they can still modify the GRUB boot label to change the root password; so we can set the menu password, and setting the menu password is also very simple, we just need to add password= password in the next line of title, and then save and exit. This way, even if you have a global password, you must enter the menu password to boot the system.

In addition, it is very insecure to encrypt GRUB in plain text directly, so MD5 is used to encrypt it. Enter grub-md5-crypt in the terminal, and the system will ask for the same password twice, after which the system will output MD5 code. You just need to copy the generated MD5 ciphertext, then set the global or menu password according to the password --md5 MD5 ciphertext format, save and exit, and restart the computer.

After pressing the e key to enter edit mode, the password has been encrypted:

The above content is the introduction of Ubuntu Grub configuration parameters. Have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserves, please pay attention to the industry information channel.

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