Grub mode

Grub mode

Reboot the server is rescue mode and then apply below fix.

# nvme list


- Fix for NVMe Servers
mount /dev/md3 /mnt/ 
mount /dev/md2 /mnt/boot/ 
mount /dev/nvme0n1p1 /mnt/boot/efi/ 
mount -o bind /dev /mnt/dev 
mount -o bind /dev/pts /mnt/dev/pts 
mount -o bind /proc /mnt/proc 
mount -o bind /run /mnt/run 
mount -o bind /sys /mnt/sys 
chroot /mnt/ 
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg 
grub2-set-default 0
exit
reboot 





To fix grub issue : http://prntscr.com/cf92at
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grub> root=(hd click on tab
grub> root=(hd0,0)
to see that exact partition on the server run below command in grub.
cat /etc/fstab

and then select any old kernel using below command 
grub> kernel /boot/vmlinuz- click on tab to see available kernel. 
grub> kernel /boot/vmlinuz-2.6.32-573.26.1.el6.x86_64 root=/dev/sda1
grub> initrd /boot/initrd.img-2.6.32-573.26.1.el6.x86_64
grub> boot
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- Fix for SATA/SSD Servers

mount /dev/md3 /mnt/ 
mount /dev/md2 /mnt/boot/ 
mount /dev/sda1 /mnt/boot/efi/ 
mount -o bind /dev /mnt/dev 
mount -o bind /dev/pts /mnt/dev/pts 
mount -o bind /proc /mnt/proc 
mount -o bind /run /mnt/run 
mount -o bind /sys /mnt/sys 
chroot /mnt/ 
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg 
grub2-set-default 0
exit
reboot