求问启动Hadoop时出现这种情况是为什么,怎么解决
Starting namenodes on [localhost]
localhost: sign_and_send_pubkey: signing failed: agent refused operation
localhost: Permission denied (publickey,password).
Starting datanodes
localhost: sign_and_send_pubkey: signing failed: agent refused operation
localhost: Permission denied (publickey,password).
Starting secondary namenodes [ubuntu]
ubuntu: sign_and_send_pubkey: signing failed: agent refused operation
ubuntu: Permission denied (publickey,password).
