前几天我在的Linux Mint 主机linuxidc.com的Virtualbox 上新安装了一个Fedora27 系统，主机名取名为fefora。
将本地.ssh目录上传到fedora上：
linuxidc@linuxidc.com ~ $ scp -r .ssh linuxidc@fedora:~/ id_rsa.pub 100% 397 0.4KB/s 00:00 known_hosts 100% 6547 6.4KB/s 00:00 id_rsa 100% 1675 1.6KB/s 00:00 linuxidc@linuxidc.com ~ $登录到主机fedora上，
linuxidc@linuxidc.com ~ $ ssh linuxidc@fedora Last login: Sat Dec 30 15:45:36 2017 from 192.168.1.4 linuxidc@redora ~ $切换到目录~/~/Public/project/com/gitee下，将clone Spring boot 项目源码:
linuxidc@redora ~ $ cd Public/project/com/gitee/ linuxidc@redora ~/Public/project/com/gitee $ ll total 8 drwxrwxr-x. 2 linuxidc lwk 4096 Dec 30 16:07 . drwxrwxr-x. 3 linuxidc lwk 4096 Dec 30 15:54 .. linuxidc@redora ~/Public/project/com/gitee $ linuxidc@redora ~/Public/project/com/gitee $ git clone git@github.com:spring-projects/spring-boot.git Cloning into 'spring-boot'... @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: UNPROTECTED PRIVATE KEY FILE! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Permissions 0644 for '/home/linuxidc/.ssh/id_rsa' 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/linuxidc/.ssh/id_rsa": bad permissions Permission denied (publickey). fatal: Could not read from remote repository. Please make sure you have the correct access rights and the repository exists. linuxidc@redora ~/Public/project/com/gitee $ 2、解决办法经查资料，发现已经有人找到了问题的解决办法：
仔细阅读了一下ssh文档和这句提示，大概的意思时ssh的私有密钥的权限开放尺度太大了，可以供人随意>欣赏了，ssh自身的策略关闭了ssh。
解决方案：将权限由0644降低为0600
chmod 0600 ~/.ssh/id_rsa
这时回过头来查看~/.ssh目录下相关文件的权限：
linuxidc@redora ~/.ssh $ ll total 28 drwx------. 2 linuxidc lwk 4096 Dec 29 18:26 . drwx------. 10 linuxidc lwk 4096 Dec 30 15:21 .. -rw-------. 1 linuxidc lwk 397 Dec 29 16:15 authorized_keys -rw-r--r--. 1 linuxidc lwk 1675 Dec 30 16:08 id_rsa -rw-r--r--. 1 linuxidc lwk 397 Dec 30 16:08 id_rsa.pub -rw-r--r--. 1 linuxidc lwk 6547 Dec 30 16:08 known_hosts linuxidc@redora ~/.ssh $果然如此，现根据上面的提示将id_rsa、id_rsa.pub、known_hosts的权限修改为只有自己可以读写。
linuxidc@redora ~/.ssh $ chmod go+r id_rsa* linuxidc@redora ~/.ssh $ chmod go+r known_hosts linuxidc@redora ~/.ssh $ ll total 28 drwx------. 2 linuxidc lwk 4096 Dec 29 18:26 . drwx------. 10 linuxidc lwk 4096 Dec 30 15:21 .. -rw-------. 1 linuxidc lwk 397 Dec 29 16:15 authorized_keys -rw-------. 1 linuxidc lwk 1675 Dec 30 16:08 id_rsa -rw-------. 1 linuxidc lwk 397 Dec 30 16:08 id_rsa.pub -rw-------. 1 linuxidc lwk 6547 Dec 30 16:08 known_hosts切换目录到~/Public/project/com/gitee，继续clone
linuxidc@redora ~ $ cd Public/project/com/gitee/ linuxidc@redora ~/Public/project/com/gitee $ git clone git@github.com:spring-projects/spring-boot.git Cloning into 'spring-boot'... remote: Counting objects: 318361, done. remote: Compressing objects: 100% (323/323), done.至此问题解决。
3、总结出现这种情况主要还是由于初学者不熟悉Linux操作命令而导致的，如果能熟练使用ssh-copy-id就不会出现这样的问题，具体命令如下：
linuxidc@linuxidc.com ~ $ ssh-copy-id -i ~/.ssh/id_rsa.pub linuxidc@fedora /usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/linuxidc/.ssh/id_rsa.pub" /usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed /usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys linuxidc@Ubuntu's password: Number of key(s) added: 1 Now try logging into the machine, with: "ssh 'linuxidc@fedora'" and check to make sure that only the key(s) you wanted were added. linuxidc@linuxidc.com ~ $