The existing docs when attempting to install CoreOS on Hetzner are a bit incomplete. This caused a bit of frustration for me so I am putting this doc together in hopes that it will help someone else.
After ordering your server you will need to log into the Hetzner server console
- Select
Key Management - Select
New Key - Give it a name and paste your public key into the
key datafield - Select
Add Key
- Select
Servers - Select your server
- Select Rescue
- For the OS, select
Linux. Select the appropriateArchitectureand thePublic keyyou added in the step above. - Select
Activate rescue system - Select
Rescue - Select
Execute a automatic hardware resetthen clickSend
You may need to wait 30s to a few minutes before the server boots into rescue mode.
Hetzner should have installed both SAS drives with an Adaptec controller to /dev/sg0 and /dev/sg1 respectively. You can inspect these using smartctl for more details.
Build the RAID1 by using the following commands
arcconf CREATE 1 LOGICALDRIVE MAX 1 0 0 0 1 noprompt
Check to see if the drives are recognized
arcconf GETCONFIG 1 PD
Ensure any metadata is cleared
arcconf TASK START 1 DEVICE 0 0 CLEAR
More info on creating a RAID on Hetzner can be found here
Ensure your private key is being forwarded and SSH to the server as root. You should enter a rescue console running Debian.
Now run
wget https://raw.githubusercontent.com/coreos/init/master/bin/coreos-install
Create a cloud-config file which will bootstrap the server. Then run
./coreos-install -d /dev/sda -C stable -c cloud-config
After a few minutes CoreOS will be installed to /dev/sda. Log back into the console and run another Execute a automatic hardware reset. Alternatively, run reboot from the rescue console.
When the system comes back up your first node in your CoreOS cluster should be available.