The DigitalOcean APi has changed and added a requirement that the key pairs must be unique. This restriction didn't exist before and directly affects jclouds, as for each node deployed by a user, jclouds will attempt to create a key pair for that node with the user's key.
Here is the email that was sent from their support team:
We're emailing today because we detected that you've used the same SSH Keys multiple times throughout your account and they need to be merged.
In approximately 48 hours we are going to be removing the duplicate keys from our database by merging them with the original key. We will also update the association with any Droplets using the duplicated keys. We will not be making any physical changes to your Droplets.
If you only manage your Droplets through our cloud control panel, you won’t notice anything different, however if you integrate with our API there’s a couple of things you should be aware of:
1. If you reference any of these SSH Keys by ID in your own application, you will need to update the ID to reflect our changes (we’ve attached a JSON file explaining the changes).
2. Going forward, SSH Key fingerprints must be unique per account. This comes with the advantage that when using APIv2 you will be able to use the SSH Key fingerprint as a unique identifier when making API calls.
Once any duplicate keys have been merged into one, you will be able to continue accessing your Droplets over SSH using the same key as before. And as always, if you have any questions related to this issue, please send us a ticket or reply to this email. https://cloud.digitalocean.com/support