I have the same trace in my logs and I disabled the key for the moment. For a quick translation because the page is in French: If you have a server with OVH, t

I have the same trace in my logs and I disabled the key for the moment. For a quick translation because the page is in French: If you have a server with OVH, they setup by default a secondary SSH key in /root/.ssh/authorized_keys2 which is allowed to access your server only from a single IPv4 and a single IPv6. This is to allow debugging of your server. It looks like the private key has been compromised and is now used to try to access the servers from another IP. Your server will not be compromised, but by security, better to disable this extra key by renaming the file "authorized_keys2.disabled". You can check your logs with a grep like this: # grep "correct" /var/log/auth.log Jul 17 21:42:49 node1 sshd[18548]: Authentication tried for root with correct \ key but not from a permitted host (host=178.63.21.XXX, ip=178.63.21.XXX).