This last weekend, I attempted to upgrade my Dedibox running Ubuntu Server from Maverick Meerkat (10.10) to Natty Narwhal (11.04). Initially, the installation seemed successful: no error messages, a quick and straightforward process. Then came the required reboot.

Once the server restarted, nothing worked, including ping, ssh, and all hosted websites.

It took me a couple of hours to fix the server and get everything running again. Here is what I did.

I first found this URL, which provided the initial steps of the process, but it didn’t work for me just yet:

sudo mkdir /mnt /md1
sudo mount /dev/md1 /mnt/md1
sudo mount /dev/md0 /mnt/md1/boot
sudo chroot /mnt/md1
update-grub

Nevertheless, it helped me identify that grub was indeed the problem. I then followed these guidelines from Dedibox’s rescue mode. A final step was missing, which I found from studying this URL:

sudo grub-install

Now, everything was back to normal: the server booted correctly, and Natty was up and running. Thanks David B. for the support!