Your job is not to waste time compiling a kernel for your server and testing it over and over again to make sure it's working properly. Booting your server in Network Mode allows you to start it from a precompiled kernel provided by OVH US.
Determining the Root Device of Your Server
In order to boot in Network Mode, you will need to tell the OVH US Manager the root device of your server. The root device is the root partition of your server. To find this information, SSH into your server and enter the command:
# cat /etc/fstab
Following is a sample output of the command:
# <file system> <mount point> <type> <options> <dump> <pass> /dev/sda3 / ext4 errors=remount-ro 0 1 /dev/sda2 /boot ext4 errors=remount-ro 0 1 /dev/sda4 swap swap defaults 0 0 proc /proc proc defaults 0 0 sysfs /sys sysfs defaults 0 0 /dev/sda1 /boot/efi vfat defaults 0 0
In this case,
/dev/sda3 is the root device since it is the root partition (denoted by
/). Now that you have determined the root device of your server, you are ready to boot your server in Network Mode.
Booting in Network Mode
To boot your server in network mode, log in to the OVH US Manager. On the left-hand sidebar, select the server in question. From the Server status tab, click the Modify button under the "Boot" section.
In the "Change the Netboot" popup, select the "Boot in network mode" option as well as the kernel you wish to use and the root device of your server. In the below screenshot, we'll configure it using our prior example where
/dev/sda3 was our root device.
Click the Next button and then click the Confirm button on the following screen to change the boot mode to Network Boot. Keep in mind that you will need to restart your server for the changes to take effect. Once you have restarted your server, it will boot from the OVH US kernel and you will be able to access and use it as you normally do.
You should now be able to use OVH US's Network Boot option as a tool to administer your server. For more information about other boot options, please check out our How to Use Rescue Mode article.