专有服务器上SSH问题的故障排除技巧

Question

我有一个问题，建立一个渠道的硬件，我们购买。我可以使用Putty（在Windows上）和Ubuntu的CLI通过SSH连接到VXworks操作系统，但是，当我使用Ruby或Python向硬件发送命令时，我会收到“connection closed by remote host”

我做了以下事情：

1. 在不同的操作系统上尝试不同的编程语言和不同的实现
2. 尝试了Ruby和Net:：SSH的不同版本，包括4.0alpha
3. 允许访问硬件22上的硬件
4. 添加超时
5. 指定特定Kex密钥
6. 缩小KEXIT的范围（我相信它被称为）
7. 联系了工程师。他们不相信这是在他们的尽头，然而他们正在提高它的链条
8. secureCRT中的Python脚本，它实际上起作用了。在
9. 使用shell通道而不是exec，后者也可以交互工作。 下一步我应该检查什么？我没主意了。在

---

一位工程师说：

"The scripts do need to have buffering between the commands. I've used securecrt for a scripting."

这是secureCRT脚本，它允许我连接到设备。我不完全相信这是否相关：

host = "x.x.x.x"
user = "admin"

def main():
    # Prompt for a password instead of embedding it in a script...
    #
    passwd = crt.Dialog.Prompt("Enter password for " + host, "Login", "", True)

    # Build a command-line string to pass to the Connect method.
    cmd = "/SSH2 /L %s /PASSWORD %s /C 3DES /M MD5 %s" % (user, passwd, host)
    crt.Session.Connect(cmd)


main()

以下是VXworks系统的日志：

^{pr2}$

下面是来自Net:：SSH的日志

[2016-05-02T13:41:48.064959 #89562] DEBUG -- net.ssh.transport.session[11a9720]: establishing connection to 10.100.0.31:22
D, [2016-05-02T13:41:48.066315 #89562] DEBUG -- net.ssh.transport.session[11a9720]: connection established
I, [2016-05-02T13:41:48.066422 #89562]  INFO -- net.ssh.transport.server_version[11a8eec]: negotiating protocol version
D, [2016-05-02T13:41:48.066440 #89562] DEBUG -- net.ssh.transport.server_version[11a8eec]: local is `SSH-2.0-Ruby/Net::SSH_4.0.0.alpha3 x86_64-linux'
D, [2016-05-02T13:41:48.069158 #89562] DEBUG -- net.ssh.transport.server_version[11a8eec]: remote is `SSH-2.0-Mocana SSH'
D, [2016-05-02T13:41:48.070131 #89562] DEBUG -- socket[11a934c]: read 424 bytes
D, [2016-05-02T13:41:48.070230 #89562] DEBUG -- socket[11a934c]: received packet nr 0 type 20 len 420
I, [2016-05-02T13:41:48.070288 #89562]  INFO -- net.ssh.transport.algorithms[11a85f0]: got KEXINIT from server
I, [2016-05-02T13:41:48.070350 #89562]  INFO -- net.ssh.transport.algorithms[11a85f0]: sending KEXINIT
D, [2016-05-02T13:41:48.070450 #89562] DEBUG -- socket[11a934c]: queueing packet nr 0 type 20 len 1156
D, [2016-05-02T13:41:48.070574 #89562] DEBUG -- socket[11a934c]: sent 1160 bytes
I, [2016-05-02T13:41:48.070615 #89562]  INFO -- net.ssh.transport.algorithms[11a85f0]: negotiating algorithms
D, [2016-05-02T13:41:48.070694 #89562] DEBUG -- net.ssh.transport.algorithms[11a85f0]: negotiated:
* kex: diffie-hellman-group1-sha1
* host_key: ssh-dss
* encryption_server: aes128-cbc
* encryption_client: aes128-cbc
* hmac_client: hmac-sha1
* hmac_server: hmac-sha1
* compression_client: none
* compression_server: none
* language_client: 
* language_server: 
D, [2016-05-02T13:41:48.070740 #89562] DEBUG -- net.ssh.transport.algorithms[11a85f0]: exchanging keys
D, [2016-05-02T13:41:48.071565 #89562] DEBUG -- socket[11a934c]: queueing packet nr 1 type 30 len 140
D, [2016-05-02T13:41:48.071659 #89562] DEBUG -- socket[11a934c]: sent 144 bytes
D, [2016-05-02T13:41:48.276487 #89562] DEBUG -- socket[11a934c]: read 448 bytes
D, [2016-05-02T13:41:48.276613 #89562] DEBUG -- socket[11a934c]: received packet nr 1 type 31 len 444
D, [2016-05-02T13:41:48.277173 #89562] DEBUG -- socket[11a934c]: queueing packet nr 2 type 21 len 20
D, [2016-05-02T13:41:48.277280 #89562] DEBUG -- socket[11a934c]: sent 24 bytes
D, [2016-05-02T13:41:48.280778 #89562] DEBUG -- socket[11a934c]: read 16 bytes
D, [2016-05-02T13:41:48.280829 #89562] DEBUG -- socket[11a934c]: received packet nr 2 type 21 len 12
D, [2016-05-02T13:41:48.281017 #89562] DEBUG -- net.ssh.authentication.session[11d6f40]: beginning authentication of `admin'
D, [2016-05-02T13:41:48.281089 #89562] DEBUG -- socket[11a934c]: queueing packet nr 3 type 5 len 28
D, [2016-05-02T13:41:48.281231 #89562] DEBUG -- socket[11a934c]: sent 52 bytes
D, [2016-05-02T13:41:48.282232 #89562] DEBUG -- socket[11a934c]: read 52 bytes
D, [2016-05-02T13:41:48.282290 #89562] DEBUG -- socket[11a934c]: received packet nr 3 type 6 len 28
D, [2016-05-02T13:41:48.282386 #89562] DEBUG -- net.ssh.authentication.session[11d6f40]: trying none
D, [2016-05-02T13:41:48.282458 #89562] DEBUG -- socket[11a934c]: queueing packet nr 4 type 50 len 44
D, [2016-05-02T13:41:48.282537 #89562] DEBUG -- socket[11a934c]: sent 68 bytes
D, [2016-05-02T13:41:48.284239 #89562] DEBUG -- socket[11a934c]: read 52 bytes
D, [2016-05-02T13:41:48.284306 #89562] DEBUG -- socket[11a934c]: received packet nr 4 type 51 len 28
D, [2016-05-02T13:41:48.284352 #89562] DEBUG -- net.ssh.authentication.session[11d6f40]: allowed methods: password
D, [2016-05-02T13:41:48.284387 #89562] DEBUG -- net.ssh.authentication.methods.none[11dfcf8]: none failed
D, [2016-05-02T13:41:48.284420 #89562] DEBUG -- net.ssh.authentication.session[11d6f40]: trying password
D, [2016-05-02T13:41:48.284489 #89562] DEBUG -- socket[11a934c]: queueing packet nr 5 type 50 len 60
D, [2016-05-02T13:41:48.284569 #89562] DEBUG -- socket[11a934c]: sent 84 bytes
D, [2016-05-02T13:41:48.295419 #89562] DEBUG -- socket[11a934c]: read 36 bytes
D, [2016-05-02T13:41:48.295559 #89562] DEBUG -- socket[11a934c]: received packet nr 5 type 52 len 12
D, [2016-05-02T13:41:48.295638 #89562] DEBUG -- net.ssh.authentication.methods.password[11de8a8]: password succeeded
D, [2016-05-02T13:41:48.295769 #89562] DEBUG -- socket[11a934c]: queueing packet nr 6 type 90 len 44
D, [2016-05-02T13:41:48.295911 #89562] DEBUG -- socket[11a934c]: sent 68 bytes
D, [2016-05-02T13:41:48.297023 #89562] DEBUG -- socket[11a934c]: read 52 bytes
D, [2016-05-02T13:41:48.297124 #89562] DEBUG -- socket[11a934c]: received packet nr 6 type 91 len 28
I, [2016-05-02T13:41:48.297203 #89562]  INFO -- net.ssh.connection.session[11e3f88]: channel_open_confirmation: 0 85460946 1000 1000
I, [2016-05-02T13:41:48.297353 #89562]  INFO -- net.ssh.connection.channel[11e3df8]: sending channel request "env"
D, [2016-05-02T13:41:48.297444 #89562] DEBUG -- socket[11a934c]: queueing packet nr 7 type 98 len 44
I, [2016-05-02T13:41:48.297579 #89562]  INFO -- net.ssh.connection.channel[11e3df8]: sending channel request "exec"
D, [2016-05-02T13:41:48.297637 #89562] DEBUG -- socket[11a934c]: queueing packet nr 8 type 98 len 28
D, [2016-05-02T13:41:48.297871 #89562] DEBUG -- socket[11a934c]: sent 120 bytes
D, [2016-05-02T13:41:49.297172 #89562] DEBUG -- socket[11a934c]: read 140 bytes
D, [2016-05-02T13:41:49.297469 #89562] DEBUG -- socket[11a934c]: read 0 bytes
I, [2016-05-02T13:41:49.297762 #89562]  INFO -- net.ssh.connection.session[11e3f88]: closing remaining channels (1 open)
D, [2016-05-02T13:41:49.297895 #89562] DEBUG -- socket[11a934c]: read 0 bytes
Net::SSH::Disconnect: connection closed by remote host