SSH using secret key file connection hint warning:unprotected private key file! (reprint)

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When using SSH to connect a remote host under CentOS 6.4, a different key is used to indicate the key file with-I, and the result is the following error:

　　

SSH specified key file hint error

Probably means that the key permission file cannot be 777 and cannot be read by other users.
After you understand the problem, modify the key file permission to 700 OK.

SSH using secret key file connection hint warning:unprotected private key file! (reprint)