Centos Rescue Mode

Centosrescue mode

In the event of a CentOS problem causing the system to fail to start again, you need to go to CentOS emergency mode for recovery. According to the author's experience, this paper summarizes the processing of common problems based on centos7rescue pattern.

1, how to enter the rescue first aid mode?

Add Rescuequie to Kernelcommand line at kernel boot time

2. What should I do if the kernel stays in noi8042 Drivec can be found at boot time?

In the kernel boot time Kernelcommand line with the Xdriver=vesaconsole=tty0init=/bin/bash option, you can avoid the presence of the kernel stop in noi8042 driver can be The phenomenon of found no longer moving forward

3. What if I find many file system commands and network functions are not available?

A. Extending the command path:

Exportpath=/usr/bin:/bin:/usr/sbin:/sbin

B. Check the NIC driver, configure the network:

Use Lsmod to check if there is a NIC driver loading, if there is no reference to the normal system load the corresponding NIC driver, such as on our system:

Modprobeigb

Then configure the network ip:ifconfigenp130s0f0 192.168.1.44

Ifupenp130s0f0

You can then synchronize the files with commands such as the SCP.

4. The file system root directory does not find how to load?

The current CENTOS7 default is to use LVM to manage the file system partition, so you need to use the Linux Volume Management command to probe the current system's physical and logical volume partitions:

Vgchange-ay/dev/centos

Vgscan

Lvscan

Once the corresponding partition is found, you can load the root and home file partitions with the Mount command, for example:

Mount/dev/md-2/Home

After the mount is complete, repair the file system with Xfs_repair:

Umount/home

umount/

Xfs_repair-d/dev/centos/root

Xfs_repair-d/dev/md-2

For the root filesystem, you need to chroot again after you mount it:

Mount/dev/md-1/mnt

Chroot/mnt

5. How can I switch between the multi-use and rescue modes of CentOS using SYSTEMD?

How to modify into rescue mode:

Update/usr/lib/systemd/system/default.target:

Set the After option to Resuce.target and set the config option to Multi-user.target.

How to modify into multi-user mode:

Update/usr/lib/systemd/system/default.target:

Set the After option to Multi-user.target and set the config option to Resuce.target.

This article is from the "Store Chef" blog, so be sure to keep this source http://xiamachao.blog.51cto.com/10580956/1881749

Centos Rescue Mode