When we upgrade the kernel (yum update or yum update kernel), in order to enter the new kernel, a server reboot is required. But sometimes we find that Centos cannot load the new kernel. The error that appears is more or less as follows:
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Entering emergency mode. Exit the shell to continue.
Type "journalctl" to view system logs.
You might want to save "/run/initramfs/rdsosreport.txt" to a USB stick or /boot
after mounting them and attach it to a bug report.
dracut:/#
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Possible solutions are as follows:
1) Enter the Client Area, then go to the Services menu > My Services > select the VPS that is experiencing problems > Manage Products > VNC COnsole
2) After accessing the VNC, the error will appear.
3) Restart the server by typing the command init 6
4) In this step, please pay close attention and do not miss it.
5) When the Boot Kernel option menu appears, select the kernel version before the upgrade, then press [Enter].
6) Then the server will load normally as usual
7) Then login to the server and run the following command
# nano /boot/grub2/grub.cfg
8) Then find the words /dev/sda1 and change them to /dev/vda1
9) Save the file and then try to restart the server again and choose the most recent kernel
