I'm using Paramiko to issue a number of commands and collect results for further analysis. Every once in a while the results from the first command are note fully returned in time and end up in the output for the second command.

I'm attempting to use recv_ready to account for this, but it is not working, so I assume I am doing something wrong. Here's the relevant code:

pause = 1def issue_command(chan, pause, cmd):# send commands and return resultschan.send(cmd + '\n')while not chan.recv_ready():time.sleep(pause)data = chan.recv(99999)ssh = paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
chan = ssh.connect(host, port=22, username=username, password=password, timeout=3,)resp1 = issue_command(chan, pause, cmd1)
resp2 = issue_command(chan, pause, cmd2)

The output for these commands is relatively small (a few sentences). Increasing the pause would likely solve the problem but is not an ideal solution.

I would use transport directly and create a new channel for each command. Then you can use something like:

def issue_command(transport, pause, command):chan = transport.open_session()chan.exec_command(command)buff_size = 1024stdout = ""stderr = ""while not chan.exit_status_ready():time.sleep(pause)if chan.recv_ready():stdout += chan.recv(buff_size)if chan.recv_stderr_ready():stderr += chan.recv_stderr(buff_size)exit_status = chan.recv_exit_status()# Need to gobble up any remaining output after program terminates...while chan.recv_ready():stdout += chan.recv(buff_size)while chan.recv_stderr_ready():stderr += chan.recv_stderr(buff_size)return exit_status, stdout, stderrssh = paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(host, port=22, username=username, password=password, timeout=3,)
transport = ssh.get_transport()
pause = 1    resp1 = issue_command(transport, pause, cmd1)
resp2 = issue_command(transport, pause, cmd2)

An even better way would be to take a list of commands and spawn a new channel for each, poll each chan's recv_ready, and suck up their stdout/stderr when output is available. :-)

Edit: There are potential issues with reading data after the command exits. Please see the comments!