我正在尝试在amazonaws上设置一个4节点集群。所有的安装、设置和配置都已完成，但在执行“start dfs.sh”命令时遇到问题。
以下是错误消息：

Starting namenodes on [ec2-13-126-215-231.ap-south-1.compute.amazonaws.com]
ec2-13-126-215-231.ap-south-1.compute.amazonaws.com: Permission denied (publickey).

datanode2: starting datanode, logging to /usr/local/hadoop/logs/hadoop-ubuntu-datanode-ip-172-31-30-218.out

datanode3: starting datanode, logging to /usr/local/hadoop/logs/hadoop-ubuntu-datanode-ip-172-31-18-165.out

datanode1: starting datanode, logging to /usr/local/hadoop/logs/hadoop-ubuntu-datanode-ip-172-31-19-66.out

Starting secondary namenodes [0.0.0.0]
0.0.0.0: Permission denied (publickey).

我也试过以下方法

sudo chown -R ubuntu /usr/local/hadoop
sudo chmod 777 /usr/local/hadoop

但仍然面临同样的错误。
请帮我解决这个错误。提前谢谢！