我使用相同的密钥和相同的安全组在同一子网下创建了两个EC2实例。只有machine1连接到公共IP。我还添加了来自同一安全组的出站ssh访问权限。我可以使用我的笔记本电脑中的putty使用我的私钥登录到一个实例（Machine1）。现在从Machine1如果我使用ssh以低于命令ssh ec2-user@secondmachine-privateip登录到Machine2，我收到错误说Permisssion被拒绝（publickey）。尝试了各种选择，但没有弄清楚我缺少什么。
在上面的命令中给出-v选项给出了以下详细信息。我没有在.ssh文件夹中生成任何新密钥或添加任何文件。
OpenSSH_6.6.1, OpenSSL 1.0.1k-fips 8 Jan 2015
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 56: Applying options for *
debug1: Connecting to xx.0.0.xx [10.0.0.140] port 22.
debug1: Connection established.
debug1: identity file /home/ec2-user/.ssh/id_rsa type -1
debug1: identity file /home/ec2-user/.ssh/id_rsa-cert type -1
debug1: identity file /home/ec2-user/.ssh/id_dsa type -1
debug1: identity file /home/ec2-user/.ssh/id_dsa-cert type -1
debug1: identity file /home/ec2-user/.ssh/id_ecdsa type -1
debug1: identity file /home/ec2-user/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/ec2-user/.ssh/id_ed25519 type -1
debug1: identity file /home/ec2-user/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.6.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1
debug1: match: OpenSSH_6.6.1 pat OpenSSH_6.6.1* compat 0x04000000
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5-etm@openssh.com none
debug1: kex: client->server aes128-ctr hmac-md5-etm@openssh.com none
debug1: kex: curve25519-sha256@libssh.org need=16 dh_need=16
debug1: kex: curve25519-sha256@libssh.org need=16 dh_need=16
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA a5:d7:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx
debug1: Host 'xx.xx.xx' is known and matches the ECDSA host key.
debug1: Found key in /home/ec2-user/.ssh/known_hosts:1
debug1: ssh_ecdsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/ec2-user/.ssh/id_rsa
debug1: Trying private key: /home/ec2-user/.ssh/id_dsa
debug1: Trying private key: /home/ec2-user/.ssh/id_ecdsa
debug1: Trying private key: /home/ec2-user/.ssh/id_ed25519
debug1: No more authentication methods to try.
Permission denied (publickey).