(base) MacBook-Air:~ root$ ssh -i /home/test.pem -p 100 root@110.0.0.0
The authenticity of host ‘[110.0.0.0]:110 ([110.0.0.0]:110)’ can’t be established.
ED25519 key fingerprint is SHA256:Txxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added ‘[110.0.0.0]:110’ (ED25519) to the list of known hosts.
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@ WARNING: UNPROTECTED PRIVATE KEY FILE! @
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Permissions 0444 for ‘/home/test.pem’ are too open.
It is required that your private key files are NOT accessible by others.
This private key will be ignored.
Load key “/home/test.pem”: bad permissions
root@110.0.0.0: Permission denied (publickey,gssapi-keyex,gssapi-with-mic).
解决：
您可以通过将权限更改为更严格的设置来解决此问题。 最安全的设置是 0400，这意味着只有文件的所有者才能读取它。 要更改权限，请使用命令：
$ chmod 0400 /home/test.pem