/root/.ssh/authorized_keys file with correct permissions (0600 for the
file, 0700 for /root/.ssh dir). Since we encourage administrators to use
public keys only if they want to access root account via ssh, might
aswell make it easier, this will be particularly useful in
managed/provisioned environments (think ansible & others).
Note that administrators might get an e-mail from security(8) if the
file suddenly appears after an update - this is of course expected :)
ok tb@ sthen@ rpe@ ajacoutot@