Python paramiko.ssh_exception.SSHException：沒有現有的會話

Question

來自此站點的示例代碼 ( https://www.kite.com/python/answers/how-to-ssh-using-paramiko-in-python )

host = "test.rebex.net"
port = 22
username = "demo"
password = "password"

command = "ls"

ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(host, port, username, password)

stdin, stdout, stderr = ssh.exec_command(command)
lines = stdout.readlines()
print(lines)

應該產生這個輸出。

['aspnet_client\n', 'pub\n', 'readme.txt\n']

憑證在此演示站點上運行良好

wolf@linux:~$ sshpass -p password ssh demo@test.rebex.net
Welcome to Rebex Virtual Shell!
For a list of supported commands, type 'help'.
demo@ETNA:/$ 
demo@ETNA:/$ ls
aspnet_client
pub
readme.txt
demo@ETNA:/$ 

但是，代碼沒有按預期工作。 我在ssh.connect(host, port, username, password)行之后ssh.connect(host, port, username, password)收到錯誤ssh.connect(host, port, username, password) 。

>>> import paramiko
>>> host = "test.rebex.net"
>>> username = "demo"
>>> password = "password"
>>> port = 22
>>> 
>>> command = "ls"
>>> 
>>> ssh = paramiko.SSHClient()
>>> ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
>>> ssh.connect(host, port, username, password)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/wolf/.local/lib/python3.8/site-packages/paramiko/client.py", line 435, in connect
    self._auth(
  File "/home/wolf/.local/lib/python3.8/site-packages/paramiko/client.py", line 764, in _auth
    raise saved_exception
  File "/home/wolf/.local/lib/python3.8/site-packages/paramiko/client.py", line 751, in _auth
    self._transport.auth_password(username, password)
  File "/home/wolf/.local/lib/python3.8/site-packages/paramiko/transport.py", line 1498, in auth_password
    raise SSHException("No existing session")
paramiko.ssh_exception.SSHException: No existing session
>>> 

讓我知道如何使它起作用。 我只想要一個簡單的 SSH 連接代碼。

更新

>>> ssh.connect(host, port, username, password, look_for_keys=False, allow_agent=False)
>>> 

參考： https : //github.com/ktbyers/netmiko/issues/1034

Answer 1

該代碼對我有用。

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當我在 Pageant 中加載了一個密鑰時，我也收到了auth_password錯誤（雖然不同 - “身份驗證失敗” ）。 在 Paramiko 嘗試使用 Pageant 密鑰后，Rebex 測試服務器似乎關閉了會話。 然后連續密碼認證失敗。 我想在你的情況下也會有類似的問題。 不同的錯誤消息可能只是由於時間差異。

starting thread (client mode): 0x33629f0
Local version/idstring: SSH-2.0-paramiko_2.6.0
Remote version/idstring: SSH-2.0-RebexSSH_5.0.7448.0
Connected (version 2.0, client RebexSSH_5.0.7448.0)
kex algos:['curve25519-sha256', 'curve25519-sha256@libssh.org', 'ecdh-sha2-nistp521', 'ecdh-sha2-nistp384', 'ecdh-sha2-nistp256', 'diffie-hellman-group16-sha512', 'diffie-hellman-group15-sha512', 'diffie-hellman-group-exchange-sha256', 'diffie-hellman-group14-sha256', 'diffie-hellman-group14-sha1', 'diffie-hellman-group-exchange-sha1'] server key:['ssh-ed25519', 'ecdsa-sha2-nistp256', 'rsa-sha2-512', 'ssh-rsa-sha256@ssh.com', 'rsa-sha2-256', 'ssh-rsa'] client encrypt:['aes256-gcm@openssh.com', 'aes128-gcm@openssh.com', 'aes256-ctr', 'aes256-cbc', 'aes192-ctr', 'aes192-cbc', 'aes128-ctr', 'aes128-cbc', 'chacha20-poly1305@openssh.com', 'twofish256-ctr', 'twofish192-ctr', 'twofish128-ctr', 'twofish256-cbc', 'twofish192-cbc', 'twofish128-cbc', 'twofish-cbc', '3des-ctr', '3des-cbc'] server encrypt:['aes256-gcm@openssh.com', 'aes128-gcm@openssh.com', 'aes256-ctr', 'aes256-cbc', 'aes192-ctr', 'aes192-cbc', 'aes128-ctr', 'aes128-cbc', 'chacha20-poly1305@openssh.com', 'twofish256-ctr', 'twofish192-ctr', 'twofish128-ctr', 'twofish256-cbc', 'twofish192-cbc', 'twofish128-cbc', 'twofish-cbc', '3des-ctr', '3des-cbc'] client mac:['hmac-sha2-512-etm@openssh.com', 'hmac-sha2-256-etm@openssh.com', 'hmac-sha2-512', 'hmac-sha2-256', 'hmac-sha1', 'hmac-sha1-96'] server mac:['hmac-sha2-512-etm@openssh.com', 'hmac-sha2-256-etm@openssh.com', 'hmac-sha2-512', 'hmac-sha2-256', 'hmac-sha1', 'hmac-sha1-96'] client compress:['none'] server compress:['none'] client lang:[''] server lang:[''] kex follows?False
Kex agreed: curve25519-sha256@libssh.org
HostKey agreed: ssh-ed25519
Cipher agreed: aes128-ctr
MAC agreed: hmac-sha2-256
Compression agreed: none
kex engine KexCurve25519 specified hash_algo <built-in function openssl_sha256>
Switch to new keys ...
Adding ssh-ed25519 host key for test.rebex.net: b'e7e445c6b8e4bbd868892786fd0158f0'
Trying SSH agent key b'3f3ae3e3b0e0ef4e5b4bfe93613557d4'
userauth is OK
Authentication (publickey) failed.
Disconnect (code 2): Authentication is already in progress.

---

如果你想避免試圖佳麗，用allow_agent的參數SSHClient.connect ：

ssh.connect(host, port, username, password, allow_agent=False)

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強制性警告：不要使用AutoAddPolicy - 這樣做AutoAddPolicy您失去對MITM 攻擊的保護。 有關正確的解決方案，請參閱Paramiko“未知服務器” 。