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Pexect in Windows Batch File > Cygwin > Python > SSH

I have a Linux box that runs Cisco IOS and need to SSH into it sometimes to reboot it. I've written a batch file that calls on Cygwin. Cygwin then calls on Python+PythonScript.
Batch File:
cd c:\cygwin64\bin
bash --login -i -c "python3 /home/Owner/uccxtesting.py"
Python Script
import pexpect
import time
import sys
server_ip = "10.0.81.104"
server_user = "administrator"
server_pass = "secretpassword"
sshuccx1 = pexpect.spawn('ssh %s#%s' % (server_user, server_ip))
sshuccx1.logfile_read = sys.stdout.buffer
sshuccx1.timeout = 180
sshuccx1.expect('.*password:')
sshuccx1.sendline(server_pass)
sshuccx1.expect('.admin:')
sshuccx1.sendline('utils system restart')
sshuccx1.expect('Enter (yes/no)?')
sshuccx1.sendline('yes')
time.sleep(30)
When I run this, it stops at Enter yes/no. This is what I'm getting:
I've seen plenty of examples of pexpect with expect, but there is some white space out beside the question mark. I just don't know how to tell python to expect it.

There may be a bug:
utils system restart prompts for force restart (https://bst.cisco.com/bugsearch/bug/CSCvw22828)
Replace time.sleep(30) with the following code to answer a possible force restart prompt. If it works, you can get rid of the try...except and print commands that I added for debugging:
try:
index = -1
while index != 0:
sshuccx1.expect_exact(['succeeded', 'force', ], timeout=300)
if index == 2:
print('Forcing restart...')
sshuccx1.sendline('yes')
print('Operation succeeded')
print(str(child.before))
except pexpect.ExceptionPexpect:
e_type, e_value, _ = sys.exc_info()
print('Error: ' + pexpect.ExceptionPexpect(e_type).get_trace())
print(e_type, e_value)
Also, change sshuccx1.expect('Enter (yes/no)?') to sshuccx1.expect_exact('Enter (yes/no)?'). The expect method tries to match a regex pattern, and it may get caught on the parentheses (see https://pexpect.readthedocs.io/en/stable/api/pexpect.html#pexpect.spawn.expect_exact)

How to check whether a shell command returned nothing or something

I am writing a script to extract something from a specified path. I am returning those values into a variable. How can i check whether the shell command has returned something or nothing.
My Code:
def any_HE():
global config, logger, status, file_size
config = ConfigParser.RawConfigParser()
config.read('config2.cfg')
for section in sorted(config.sections(), key=str.lower):
components = dict() #start with empty dictionary for each section
#Retrieving the username and password from config for each section
if not config.has_option(section, 'server.user_name'):
continue
env.user = config.get(section, 'server.user_name')
env.password = config.get(section, 'server.password')
host = config.get(section, 'server.ip')
print "Trying to connect to {} server.....".format(section)
with settings(hide('warnings', 'running', 'stdout', 'stderr'),warn_only=True, host_string=host):
try:
files = run('ls -ltr /opt/nds')
if files!=0:
print '{}--Something'.format(section)
else:
print '{} --Nothing'.format(section)
except Exception as e:
print e
I tried checking 1 or 0 and True or false but nothing seems to be working. In some servers, the path '/opt/nds/' does not exist. So in that case, nothing will be there on files. I wanted to differentiate between something returned to files and nothing returned to files.

First, you're hiding stdout.
If you get rid of that you'll get a string with the outcome of the command on the remote host. You can then split it by os.linesep (assuming same platform), but you should also take care of other things like SSH banners and colours from the retrieved outcome.

As perror commented already, the python subprocess module offers the right tools.
https://docs.python.org/2/library/subprocess.html
For your specific problem you can use the check_output function.
The documentation gives the following example:
import subprocess
subprocess.check_output(["echo", "Hello World!"])
gives "Hello World"

plumbum is a great library for running shell commands from a python script. E.g.:
from plumbum.local import ls
from plumbum import ProcessExecutionError
cmd = ls['-ltr']['/opt/nds'] # construct the command
try:
files = cmd().splitlines() # run the command
if ...:
print ...:
except ProcessExecutionError:
# command exited with a non-zero status code
...
On top of this basic usage (and unlike the subprocess module), it also supports things like output redirection and command pipelining, and more, with easy, intuitive syntax (by overloading python operators, such as '|' for piping).

In order to get more control of the process you run, you need to use the subprocess module.
Here is an example of code:
import subprocess
task = subprocess.Popen(['ls', '-ltr', '/opt/nds'], stdout=subprocess.PIPE)
print task.communicate()

How can I make my custom shell work with ssh?

I'm making a custom shell in Python for a very limited user on a server, who is logged in via ssh with a public key authentication. They need to be able to run ls, find -type d, and cat in specific directories with certain limitations. This works fine if you run something like ssh user#server -i keyfile, because you see the interactive prompt, and can run those commands. However, something like ssh user#server -i keyfile "ls /var/log" doesn't. ssh simply hangs, with no response. By using the -v switch I've found that the connection is succeeding, so the problem is in my shell. I'm also fairly certain that the script isn't even being started, since print sys.argv at the beginning of the program does nothing. Here's the code:
#!/usr/bin/env python
import subprocess
import re
import os
with open(os.devnull, 'w') as devnull:
proc = lambda x: subprocess.Popen(x, stdout=subprocess.PIPE, stderr=devnull)
while True:
try:
s = raw_input('> ')
except:
break
try:
cmd = re.split(r'\s+', s)
if len(cmd) != 2:
print 'Not permitted.'
continue
if cmd[0].lower() == 'l':
# Snip: verify directory
cmd = proc(['ls', cmd[1]])
print cmd.stdout.read()
elif cmd[0].lower() == 'r':
# Snip: verify directory
cmd = proc(['cat', cmd[1]])
print cmd.stdout.read()
elif cmd[0].lower() == 'll':
# Snip: verify directory
cmd = proc(['find', cmd[1], '-type', 'd'])
print cmd.stdout.read()
else:
print 'Not permitted.'
except OSError:
print 'Unknown error.'
And here's the relevant line from ~/.ssh/authorized_keys:
command="/path/to/shell $SSH_ORIGINAL_COMMAND" ssh-rsa [base-64-encoded-key] user#host
How can I make the shell script when the command is passed on the command line so it can be used in scripts without starting an interactive shell?

The problem with ssh not responding is related to the fact that ssh user#host cmd does not open a terminal for the command being run. Try calling ssh user#host -t cmd.
However, even if you pass the -t option, you'd still have another problem with your script: it only works interactively and totally ignores the $SSH_ORIGINAL_PROGRAM being passed. A naive solution would be to check sys.argv and if its bigger than 1 you don't loop forever, and instead only execute whatever command you have in it.

Python 2.7: wmi module: Creating an interactive process on a remote system

Creating an installer for possible remote systems so that if they do not have something installed, it will start the autorun.exe on their desktop (sure it would be easy to give them the link and they could click start and run... but this would be 100% better if it was done for them!)
Heres the model I have been using and I should mention that I am testing between both a windows 7 and XP machine, although I don't think its too big of a deal.
import wmi
import win32com.client
def Copy_Program(computer=None, environment="Production"):
Oracle_install = r'\\server1\Install\Oracle\Oracle9i_Disk1\autorun\autorun.exe'
""" BELOW PROCESS SHOWS UP IN TASKMANAGER, but I NEED IT TO BE INTERACTIVE.
wmi = win32com.client.GetObject ("winmgmts:\\\\"+computer+"\\root\\cimv2")
win32_process = wmi.Get ("Win32_Process")
in_parameters = win32_process.Methods_ ("Create").InParameters
in_parameters.Properties_ ('CommandLine').Value = "notepad.exe"
result = win32_process.ExecMethod_ ("Create", in_parameters)
"""
SW_SHOWMINIMIZED = 1
c = wmi.WMI (computer)
startup = c.Win32_ProcessStartup.new (ShowWindow=SW_SHOWMINIMIZED)
pid, result = c.Win32_Process.Create (
CommandLine=Oracle_install,
ProcessStartupInformation=startup
)
if __name__ == '__main__':
Copy_Program(computer = "D02659")
Now as Mr Tim Golden had mentioned in the docs... remoting to another machine is pretty simple... you just
c = wmi.WMI("REMOTE_COMPUTER")
and away you go...
and technically it does work, but its not interactive for some reason... I've also tinkered with the SW_SHOWMINIMIZED values, but I can't seem to understand what I'm doing wrong. I have domain admin, so it shouldn't be an issue... especially since I am logged into both systems at the same time... weird.
Anyhow, help is very much appreciated!

This is a limitation of the Create method of the Win32_Process WMI class
For security reasons the Win32_Process.Create method cannot be used to
start an interactive process remotely.
Windows 2000 Professional with SP2 and earlier, Windows NT, and Windows 98/95
Win32_Process.Create can create an interactive process
remotely.

PSEXEC looks like its the only viable solution here unfortunately... as much as I hate to invoke a 3rd party tool, this works well.
import subprocess
import getpass
Oracle = r'\\server\z$\deploy\Install\Oracle\Oracle9i_Disk1\Oracle9i_Disk1\autorun\autorun.exe'
def Craft_Startup(COMPUTER, COMMAND):
UNAME="DOMAIN\\"+getpass.getuser()
PASSWD = getpass.getpass()
subprocess.Popen("psexec -u "+ UNAME +" -p " + PASSWD + " \\\\"+COMPUTER+" -i " + COMMAND)
if __name__ == '__main__':
COMPUTER = 'P04213'
COMMAND = Oracle
Craft_Startup(COMPUTER, 'cmd.exe /c start ' + COMMAND)
So the necessity here is to put psexec in the system32 folder or... specify the path if you'd like

Using os.forkpty() to create a pseudo-terminal to ssh to a remote server and communicate with it

I'm trying to write a python script that can ssh into remote server and can execute simple commands like ls,cd from the python client. However, I'm not able to read the output from the pseudo-terminal after successfully ssh'ing into the server. Could anyone please help me here so that I could execute some commands on the server.
Here is the sample code:
#!/usr/bin/python2.6
import os,sys,time,thread
pid,fd = os.forkpty()
if pid == 0:
os.execv('/usr/bin/ssh',['/usr/bin/ssh','user#host',])
sys.exit(0)
else:
output = os.read(fd,1024)
print output
data = output
os.write(fd,'password\n')
time.sleep(1)
output = os.read(fd,1024)
print output
os.write(fd,'ls\n')
output = os.read(fd,1024)
print output
Sample output:
user#host's password:
Last login: Wed Aug 24 03:16:57 2011 from 1x.x.x.xxxx
-bash: ulimit: open files: cannot modify limit: Operation not permitted
host: /home/user>ls

I'd suggest trying the module pexpect, which is built exactly for this sort of thing (interfacing with other applications via pseudo-TTYs), or Fabric, which is built for this sort of thing more abstractly (automating system administration tasks on remote servers using SSH).
pexpect: http://pypi.python.org/pypi/pexpect/
Fabric: http://docs.fabfile.org/en/1.11/

As already stated, better use public keys. As I use them normally, I have changed your program so that it works here.
#!/usr/bin/python2.6
import os,sys,time,thread
pid,fd = os.forkpty()
if pid == 0:
os.execv('/usr/bin/ssh',['/usr/bin/ssh','localhost',])
sys.exit(0)
else:
output = os.read(fd,1024)
print output
os.write(fd,'ls\n')
time.sleep(1) # this is new!
output = os.read(fd,1024)
print output
With the added sleep(1), I give the remote host (or, in my case, not-so-remote host) time to process the ls command and produce its output.
If you send ls and read immediately, you only read what is currently present. Maybe you should read in a loop or so.
Or you just should do it this way:
import subprocess
sp = subprocess.Popen(("ssh", "localhost", "ls"), stdout=subprocess.PIPE)
print sp.stdout.read()