Command Executed with Paramiko Does Not Produce Any Output

Command executed with Paramiko does not produce any output

If you get no output on stdout, it is usually because the command fails to start.

Read stderr to check for any errors.

print(stderr.readlines())

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Quite often the error is "<command> not found". For that see

Some Unix commands fail with "<command> not found", when executed using Python Paramiko exec_command

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If you are connecting to a device, see also Executing command using Paramiko exec_command on device is not working.

A command does not finish when executed using Python Paramiko exec_command

You read only one line of the output.

logging.debug(f'ssh_stdout: {ssh_stdout.readline()}')

If the remote program produces lot of output, as soon as its output buffer fills in, the program hangs on the next attempt to write some output.

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If you want the program to finish, you have to keep reading the output.

The simplest way is to use readlines or read:

print(stdout.read())

But that's inefficient for large outputs like yours.

Instead you can read the output line by line:

for line in stdout:
    print(line.strip())

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It gets more complicated, when the commands produces also an error output, as then you have to read both output streams.
See Paramiko ssh die/hang with big output.

And you should check the error output in any case, for good error handling. See also:

Command executed with Paramiko does not produce any output

Python : Paramiko - channel.exec_command not returning output intermittently

It's probably a race condition. The exit_status_ready can return true if the command has finished, even if you have not read its complete output yet.

The correct code is like:

while True:
    exited = channel.exit_status_ready()
    if channel.recv_ready():
        data = channel.recv(1024)
        LOG.debug(data.decode())
        while data:
            contents.write(data.decode())
            data = channel.recv(1024)
            LOG.debug(data.decode())
    if channel.recv_stderr_ready():
        error_buff = channel.recv_stderr(1024)
        LOG.debug(error_buff.decode())
        while error_buff:
            error.write(error_buff.decode())
            error_buff = channel.recv_stderr(1024)
            LOG.debug(error_buff.decode())
    if exited:
        break

Paramiko: read from standard output of remotely executed command

You have closed the connection before reading lines:

import paramiko
client=paramiko.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
com="ls ~/desktop"
client.connect('MyIPAddress',MyPortNumber, username='username', password='password')
output=""
stdin, stdout, stderr = client.exec_command(com)

print "ssh succuessful. Closing connection"
stdout=stdout.readlines()
client.close()
print "Connection closed"

print stdout
print com
for line in stdout:
    output=output+line
if output!="":
    print output
else:
    print "There was no output for this command"

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