Am looking for a python script that can Open an already saved session in Putty and execute few commands in the SSH Session and make sure it went through fine.
I could Open the saved session (10.2.0.14) with a bat script
putty.bat
putty.exe -load 10.2.0.14 -l ubuntu
puttytest.py
import subprocess
try:
process = subprocess.run(["C:\\Users\\test\\Desktop\\putty.bat"], check=True, stdout=subprocess.PIPE, universal_newlines=True)
print("stdout:", process.stdout)
except Exception as e:
print("subprocess call error in open putty command")
print(str(e))
Looking further how to execute a few commands on the SSH session and make sure it went through fine.
Related
I am trying to run my local bash script on remote server without copying it into remote server. It is as simple as following for test purpose. There are more than a few servers where it runs perfectly, but in some server running tcsh, there is an issue. How do I invoke bash, if following does not work. Below is dummy test.sh
#!/bin/bash
a=test
echo $a
echo $SHELL
I am using Python Paramiko exec_command for remote execution as following:
my_script = open("test.sh").read()
stdin, stdout, stderr = ssh.exec_command(my_script, timeout=15)
print(stdout.read().decode())
err = stderr.read().decode()
if err:
print(err)
Given, that connection works and same script works for other servers with bash default shell.
This is the output that i get:
/bin/tcsh
printing from errors
a=test: Command not found.
a: Undefined variable.
The #!/bin/bash is a comment. Sending it to a remote shell as a command has no effect.
You have to execute /bin/bash on the server and send your script to it:
stdin, stdout, stderr = ssh.exec_command("/bin/bash", timeout=15)
stdin.write(my_script)
Also, you have to exit the shell at the end of your script, otherwise it will never end.
Related question:
Pass arguments to a bash script stored locally and needs to be executed on a remote machine using Python Paramiko
I am trying to run my local bash script on remote server without copying it into remote server. It is as simple as following for test purpose. There are more than a few servers where it runs perfectly, but in some server running tcsh, there is an issue. How do I invoke bash, if following does not work. Below is dummy test.sh
#!/bin/bash
a=test
echo $a
echo $SHELL
I am using Python Paramiko exec_command for remote execution as following:
my_script = open("test.sh").read()
stdin, stdout, stderr = ssh.exec_command(my_script, timeout=15)
print(stdout.read().decode())
err = stderr.read().decode()
if err:
print(err)
Given, that connection works and same script works for other servers with bash default shell.
This is the output that i get:
/bin/tcsh
printing from errors
a=test: Command not found.
a: Undefined variable.
The #!/bin/bash is a comment. Sending it to a remote shell as a command has no effect.
You have to execute /bin/bash on the server and send your script to it:
stdin, stdout, stderr = ssh.exec_command("/bin/bash", timeout=15)
stdin.write(my_script)
Also, you have to exit the shell at the end of your script, otherwise it will never end.
Related question:
Pass arguments to a bash script stored locally and needs to be executed on a remote machine using Python Paramiko
I want to write a script that opens the cmd shell (windows) issues a command then retrieves the output and sends another command. So far I'm able to send a command and retrieve the output but the session closes and I don't want that. I want to keep sending commands to the same cmd window (session).
from subprocess import check_output
command = 'dir C:'
out_put = check_output(command, shell=True).decode()
print(out_put)
I can execute a script from python environment locally using subprocess but due to cross platform issues, I have to execute it on a remote server and get back the results on my local machine.
The directory parserpath contains some third party modules that can be executed using a script run.sh present in parserpath directory. However this parserpath directory is present on a remote server.
This is what I have, but this will work only if parserpath is a local directory. How can I ssh to a remote directory and run the script run.sh?
def run_parser(filename):
current_dir = os.getcwd()
parser_path="/parserpath"
os.chdir(parser_path)
subprocess.call("./run.sh " + filename, shell=True)
os.chdir(current_dir)
With most linux shells, you can run a command in a different working directory by executing a subshell as in
/home/usr> (cd /usr/local/bin;pwd)
/usr/local/bin
/home/usr>
You can do the same thing through ssh to the remote system. Depending on which ssh client you use, you may thin that up a bit. For instance, with paramikos exec_command, a new remote shell is created for each command so cd /path/on/remote/machine;./run.sh is sufficient.
A minimalist example for paramiko on python 2.x is
import sys
import paramiko
try:
hostname, username, password, targetpath = sys.argv[1:5]
except ValueError:
print("Failed, call with hostname username password targetpath")
command = "cd {};pwd".format(targetpath)
print("Command to send: {}".format(command))
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(hostname=hostname, username=username, password=password)
stdin, stdout, stderr = ssh.exec_command("cd {};pwd".format(targetpath))
print(stdout.read())
ssh.close()
python3 should be similar. There are other options like libssh2 bindings for python, pexpects ssh support and etc...
Use SSH keys to automate the process of logging in via SSH. Here is the following code to execute a script remotely.
ssh = subprocess.Popen(["ssh", "%s" % HOST, COMMAND],
shell=False,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
Try, ssh user#host sh path/run.sh
Trying to monitor the available physical disc space of a remote machine using a python script, which executes the df -h . command using subprocess.popen.
import subprocess
import time
command = 'ssh remoteserver "df -h ."'
while True:
proc = subprocess.Popen(command,shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output,err=proc.communicate()
print output
print err
time.sleep(60)
The script runs fine and prints the output to the terminal when run from command line
$> python2.7 script.py
Filesystem Size Used Avail Use% Mounted on
remoteserver:/home/user
555G 447G 109G 81% /home
The scripts does not produce any output or seems to be blocking when the script is started with nohup command.
$> nohup python2.7 script.py &
Would like the script to work and fetch the disc space of remote machine using the above script when started in nohup.
I'm not 100% sure of the underlying issue here, but when you invoke NOHUP in the shell, it's disconnected some of the STDIN/STDOUT from the terminal process, which I suspect it causing some of this interactions you're seeing.
Given that you're doing this from a remote machine, I'd actually recommend you look at using something like Fabric as a library to do what you're after. It's pretty straightforward, and does most of the handling of terminal sessions as well as closing things down nicely for you when you're complete.
something like:
from fabric import api
from fabric.api import env
import fabric
env.host_string = '%s#%s' % (username, remote_host)
env.disable_known_hosts = True
env.password = password
fabric.state.output['stdout'] = False
fabric.state.output['stderr'] = False
results = api.run('df -h')
You might try sending stdin=subprocess.PIPE to the subprocess command, then calling proc.stdin.close() on the next line, before the communicate() call. Or you can try changing the command to 'ssh remoteserver "df -h ." </dev/null'. Others report using FNULL = open(os.devnull, 'r') and passing in FNULL to the stdin= argument, but I'm not sure if you need to call FNULL.close() after or not.
SSH is most likely waiting for input for some reason when it is run from nohup. Perhaps it is unable to authenticate in the nohup environment and is asking for password input?
To make sure SSH is not waiting for input, try adding -o "BatchMode yes" to the ssh command and see if there are some clues in the output/error from the subprocess communicate call.