所以，我运行了一个ubuntu ec2实例，想要建立一个ssh（我是一个Ubuntu 16.04用户）。但是，当我尝试：
时，我认为我没有得到正确的答案huzeyfekiran@huzeyfekiran-ThinkPad-L450:~/Downloads$ chmod 400 mykeypair.pem
huzeyfekiran@huzeyfekiran-ThinkPad-L450:~/Downloads$ ssh -i mykeypair.pem ubuntu@ec2-18-219-42-124.us-east-2.compute.amazonaws.com
The authenticity of host 'ec2-18-219-42-124.us-east-2.compute.amazonaws.com (18.219.42.124)' can't be established.
ECDSA key fingerprint is SHA256:T9J5/BH9RmALnv/6n4rUu0tw8nIFHn8zYvM9BwwP3fA.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'ec2-18-219-42-124.us-east-2.compute.amazonaws.com,18.219.42.124' (ECDSA) to the list of known hosts.
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.4.0-1047-aws x86_64)
* Documentation:
* Management:
* Support:
Get cloud support with Ubuntu Advantage Cloud Guest:
0 packages can be updated.
0 updates are security updates.
The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.
我认为我没有得到正确的回应，因为当我尝试通过jupyter笔记本连接到ec2实例时，浏览器无法建立连接，我确信我已关闭防火墙。那么，SSH有问题吗？