我曾通过 ubuntu ssh 连接多台计算机。但是出于某种原因，我无法从同一网络中的同一台机器 ssh 连接我自己的计算机（这台特定的计算机）。我也可以通过 ssh 连接其他计算机，但不能连接这台特定的计算机。
我的主机名（出于安全原因有所不同）
lab.dept.uni.ece
我的账户名是
user
做一个简单的：
ssh [email protected]
应该允许我 ssh 到我自己的计算机，但当我输入用户名和密码时，它显示“权限被拒绝”，好像我的密码（或可能是用户名？）是错误的。它没有抱怨主机名或用户名，所以我假设它们是正确的。有什么方法可以检查吗？另一方面，也许我在计算机上设置了某种 sshing 阻止？
另外，我记得我实验室的一位博士后也告诉我，我的电脑上发生了一些奇怪的事情，因为当他想 ssh 到他的帐户时（我们在我的计算机上为他创建了一个帐户，看看他是否可以使用他的用户/密码 ssh 到该帐户），他实际上无法做到。
ssh 已安装。我该怎么做？
ssh -vv 的输出[电子邮件保护]
OpenSSH_5.9p1 Debian-5ubuntu1.4, OpenSSL 1.0.1 14 Mar 2012
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to lab.dept.uni.edu [128.111.113.132] port 22.
debug1: Connection established.
debug1: identity file /home/user/.ssh/id_rsa type -1
debug1: identity file /home/user/.ssh/id_rsa-cert type -1
debug1: identity file /home/user/.ssh/id_dsa type -1
debug1: identity file /home/user/.ssh/id_dsa-cert type -1
debug1: identity file /home/user/.ssh/id_ecdsa type -1
debug1: identity file /home/user/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9p1 Debian-5ubuntu1.4
debug1: match: OpenSSH_5.9p1 Debian-5ubuntu1.4 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1.4
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],[email protected],[email protected],ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,[email protected],hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA 86:b8:8e:c5:a5:53:5a:df:26:99:0b:90:9f:4b:91:8e
debug1: Host 'lab.dept.uni.edu' is known and matches the ECDSA host key.
debug1: Found key in /home/user/.ssh/known_hosts:9
debug1: ssh_ecdsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/user/.ssh/id_rsa ((nil))
debug2: key: /home/user/.ssh/id_dsa ((nil))
debug2: key: /home/user/.ssh/id_ecdsa ((nil))
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Trying private key: /home/user/.ssh/id_rsa
debug1: Trying private key: /home/user/.ssh/id_dsa
debug1: Trying private key: /home/user/.ssh/id_ecdsa
debug2: we did not send a packet, disable method
debug1: Next authentication method: password
[email protected]'s password:
debug2: we sent a password packet, wait for reply
debug1: Authentications that can continue: publickey,password
Permission denied, please try again.
我还认为用户名可能是一个问题，因为我有一个用户名：“user”和“User”，其中一个是小写，另一个是大写。然而，这似乎不是问题，因为我无法通过 ssh 连接到我刚刚创建的新用户名（如“bob”），而且我也知道密码。
答案1
您是从客户端的角度来看待这一点的，但由于您是尝试登录的 PC 的所有者，因此您可以通过启动远程控制带有调试选项的守护进程：
service ssh stop
/usr/sbin/sshd -Dd
（德防止守护进程分离，d将其置于调试模式）。现在您可以尝试从另一台电脑登录，并查看守护进程的输出以及拒绝您访问的原因。
您应该记住，客户端并非旨在提供大量信息，因为除了合法的调试目的之外，恶意攻击者还可能利用它们来提高入侵毫无戒心的受害者计算机的机会。另一方面，守护进程本身的调试消息只能由 PC 的所有者访问，因此它们将用于合法用途。这就是服务器端消息更具信息性的原因。
希望这将为您/我们提供足够的信息以便在下一次迭代中调试问题。