刚刚设置了一个新的 EC2 实例，下载了 pem 文件，但目前无法进入框。我正在使用命令...
$ ssh -i .ssh/key.pem ubuntu@ec2-176-34-183-***.eu-west-1.compute.amazonaws.com
...并要求输入密码。但我生成密钥对时没有指定密码！为什么会发生这种情况？
无论如何，我仔细研究了一下，找到了如何从密钥中删除密码：
$ openssl rsa -in key.pem -out key-nopass.pem
虽然密码确实被删除了，但仍然没有什么惊喜。这是我的详细输出：
OpenSSH_5.3p1 Debian-3ubuntu7, OpenSSL 0.9.8k 25 Mar 2009
debug1: Reading configuration data /home/bob/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to ec2-176-34-183-***.eu-west-1.compute.amazonaws.com [176.34.183.***] port 22.
debug1: Connection established.
debug1: identity file key-nopass.pem type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3p1 Debian- 3ubuntu7
debug1: match: OpenSSH_5.3p1 Debian-3ubuntu7 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.3p1 Debian-3ubuntu7
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host 'ec2-176-34-183-***.eu-west-1.compute.amazonaws.com' is known and matches the RSA host key.
debug1: Found key in /home/bob/.ssh/known_hosts:1
debug1: ssh_rsa_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: key-nopass.pem
debug1: read PEM private key done: type RSA
debug1: Authentications that can continue: publickey
debug1: No more authentication methods to try.
Permission denied (publickey).
顺便说一下，pem 文件权限设置为 600。为什么我无法登录？
答案1
这里可能发生了一些事情。首先，您似乎正在尝试登录 ubuntu 用户。您确定该用户存在并且该密钥对与该用户相关联吗？我会尝试以 root 身份登录，看看是否可行。
另一种可能是你的私钥错误。你是直接下载的还是通过复制/粘贴创建的？如果是后者，那么你可能没有正确粘贴。
权限正确，因此一定是上述情况之一。私钥不在您尝试登录的 authorized_keys 中，或者您拥有错误的/损坏的密钥。