python scripts for router - python

I am a beginner. I use paramiko to push configuration to devices. I use anaconda on a windows machine. How do I use database and proper formatting to take the output? Please suggest some learning on exception handling.
import paramiko
import sys
import subprocess
import time
vm = paramiko.SSHClient()
vm.set_missing_host_key_policy(paramiko.AutoAddPolicy())
vm.connect('x.x.x.x', username='your_user_name', password='your_password')
rtrlist = ["a","b"]
for n in rtrlist:
remote_conn_pre=paramiko.SSHClient()
remote_conn_pre.set_missing_host_key_policy(paramiko.AutoAddPolicy())
remote_conn_pre.connect(n, port=22, username='your_user_name', password='your_password', look_for_keys=False, allow_agent=False)
remote_conn.send("conf t\n")
time.sleep(.5)
output = remote_conn.recv(65535)
print (output)
remote_conn.send("flow exporter Netflow-Exporter-Mazu\n")
time.sleep(.5)
output = remote_conn.recv(65535)
print (output)
remote_conn.send("do wr\n")
time.sleep(.5)
output = remote_conn.recv(65535)
print (output)
vm.close()

Used mongodb, pymongo, paramiko, get_transport().
Was able to pick data from database.
Was able to dry run . Having few hiccups on the exceptions. Anyhow, I am able complete current task.

Related

Command output is corrupted when executed using Python Paramiko exec_command

I'm a software tester, trying to verify that the log on a remote QNX (a BSD variant) machine will contain the correct entries after specific actions are taken. I am able to list the contents of the directory in which the log resides, and use that information in the command to read (really want to use tail -n XX <file>) the file. So far, I always get a "(No such file or directory)" when trying to read the file.
We are using Froglogic Squish for automated testing, because the Windows UI (that interacts with the server piece on QNX) is built using Qt extensions for standard Windows elements. Squish uses Python 2.7, so I am using Python 2.7.
I am using paramiko for the SSH connection to the QNX server. This has worked great for sending commands to the simulator piece that also runs on the QNX server.
So, here's the code. Some descriptive names have been changed to avoid upsetting my employer.
import sys
import time
import select
sys.path.append(r"C:\Python27\Lib\site-packages")
sys.path.append(r"C:\Python27\Lib\site-packages\pip\_vendor")
import paramiko
# Import SSH configuration variables
ssh_host = 'vvv.xxx.yyy.zzz'
thelog_dir = "/logs/the/"
ssh_user = 'un'
ssh_pw = 'pw'
def execute_Command(fullCmd):
outptLines = []
#
# Try to connect to the host.
# Retry a few times if it fails.
#
i = 1
while True:
try:
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(ssh_host, 22, ssh_user, ssh_pw)
break
except paramiko.AuthenticationException:
log ("Authentication failed when connecting to %s" % ssh_host)
return 1
except:
log ("Could not SSH to %s, waiting for it to start" % ssh_host)
i += 1
time.sleep(2)
# If we could not connect within time limit
if i == 30:
log ("Could not connect to %s. Giving up" % ssh_host)
return 1
# Send the command (non-blocking?)
stdin, stdout, stderr = ssh.exec_command(fullCmd, get_pty=True)
for line in iter(stdout.readline, ""):
outptLines.append(line)
#
# Disconnect from the host
#
ssh.close()
return outptLines
def get_Latest_Log():
fullCmd = "ls -1 %s | grep the_2" %thelog_dir
files = execute_Command(fullCmd)
theFile = files[-1]
return theFile
def main():
numLines = 20
theLog = get_Latest_Log()
print("\n\nThe latest log is %s\n\n" %theLog)
fullCmd = "cd /logs/the; tail -n 20 /logs/the/%s" %theLog
#fullCmd = "tail -n 20 /logs/the/%s" %theLog
print fullCmd
logLines = execute_Command(fullCmd)
for line in logLines:
print line
if __name__ == "__main__":
# execute only if run as a script
main()
I have tried to read the file using both tail and cat. I have also tried to get and open the file using Paramiko's SFTP client.
In all cases, the response of trying to read the file fails -- despite the fact that listing the contents of the directory works fine. (?!) And BTW, the log file is supposed to be readable by 'world'. Permissions are -rw-rw-r--.
The output I get is:
"C:\Users\xsat086\Documents\paramikoTest>python SSH_THE_MsgChk.py
The latest log is the_20210628_115455_205.log
cd /logs/the; tail -n 20 /logs/the/the_20210628_115455_205.log
(No such file or directory)the/the_20210628_115455_205.log"
The file name is correct. If I copy and paste the tail command into an interactive SSH session with the QNX server, it works fine.
Is it something to do with the 'non-interactive' nature of this method of sending commands? I read that some implementations of SSH are built upon a command that offers a very limited environment. I don't see how that would impact this tail command.
Or am I doing something stupid in this code?
I cannot really explain completely, why you get the results you get.
But in general a corrupted output is a result of enabling and not handling terminal emulation. You enable the terminal emulation using get_pty=True. Remove it. You should not use the terminal emulation, when automating command execution.
Related question:
Is there a simple way to get rid of junk values that come when you SSH using Python's Paramiko library and fetch output from CLI of a remote machine?

Python, Linux: How to execute multiple commands using pysftp

Here I am trying to execute commands on remote server and getting back its output, for every command, but it need a saperate connection, but if I create saperate connection or session, its responding me very slowly,
The code that I am trying run is, But its not working :
import pysftp
import paramiko
commandlist = ("ls", "uname -a","whoami")
ans = []
sftp = pysftp.Connection("localhost",username="root",password="123456",port=22)
for i in commandlist:
try:
out = sftp.execute(i)
ans.append(out)
except (paramiko.ssh_exception.AuthenticationException,paramiko.ssh_exception.SSHException), e:
ans.append(e)
return ans
working code is:
import pysftp
import paramiko
commandlist = ("ls", "uname -a")
ans = []
for i in commandlist:
try:
sftp = pysftp.Connection("localhost",username="root",password="123456",port=222)
out = sftp.execute(i)[0]
ans.append(out)
except (paramiko.ssh_exception.AuthenticationException,paramiko.ssh_exception.SSHException), e:
ans.append(e)
return ans
now here its creating connection for every command to execute,
please help me, let me know if this can be done by other liberary like paramiko or fabric and how.
Thanks.

ssh/login to a buildserver on the network and logout

I am trying to ssh into a buildserver on the network and run some commands and logout of the server,i have looked at other posts
and written the following code but its not working?can anyone suggest what is wrong or is there a better way to accomplish this?thanks in advance
import os
import sys
import pexpect
#os.system(ssh username#buildservername)
child = pexpect.spawn('ssh username#buildservername', logfile=sys.stdout)
#child.expect('Are you sure you want to continue connecting (yes/no)?')
#child.sendline('yes')
#child.expect('password:')
child.sendline('password')
cmd = 'hostname'
os.system(cmd)
os.chdir('//local/mnt/workspace')
os.mkdir('newdir')
os.getcwd()
You may take a look a the Paramiko library, especialy the SFTPClient
It's a native Python SSHv2 protocol library.
import paramiko
ssh = paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.connect('buildservername', username='yadomi', password='password')
sftp = ssh.open_sftp()
sftp.chdir('/local/mnt/workspace')
sftp.mkdir('newdir')

Python paramiko module using multiple commands

I have a class that creates the connection. I can connect and execute 1 command before the channel is closed. On another system i have i can execute multiple commands and the channel does not close. Obviously its a config issue with the systems i am trying to connect to.
class connect:
newconnection = ''
def __init__(self,username,password):
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
try:
ssh.connect('somehost', username=username,password=password,port=2222,timeout=5)
except:
print "Count not connect"
sys.exit()
self.newconnection = ssh
def con(self):
return self.newconnection
Then i use 'ls' command just to print some output
sshconnection = connect('someuser','somepassword').con()
stdin, stdout, stderr = sshconnection.exec_command("ls -lsa")
print stdout.readlines()
print stdout
stdin, stdout, stderr = sshconnection.exec_command("ls -lsa")
print stdout.readlines()
print stdout
sshconnection.close()
sys.exit()
After the first exec_command runs it prints the expected output of the dir list. When i print stdout after the first exec_command it looks like the channel is closed
<paramiko.ChannelFile from <paramiko.Channel 1 (closed) -> <paramiko.Transport at 0x2400f10L (cipher aes128-ctr, 128 bits) (active; 0 open channel(s))>>>
Like i said on another system i am able to keep running commands and the connection doesn't close. Is there a way i can keep this open? or a better way i can see the reason why it closes?
edit: So it looks like you can only run 1 command per SSHClient.exec_command... so i decided to get_transport().open_session() and then run a command. The first one always works. The second one always fails and the scripts just hangs
With just paramiko after the exec_command executes the channel is closed and the ssh returns an auth prompt.
Seems its not possible with just paramiko, try fabric or another tool.
** fabric did not work out too.
Please see the following referece as it provides a way to do this in Paramiko:
How do you execute multiple commands in a single session in Paramiko? (Python)
it's possible with netmiko (tested on windows).
this example is written for connecting to cisco devices but the principle is adaptable for others as well.
import netmiko
from netmiko import ConnectHandler
import json
def connect_enable_silent(ip_address,ios_command):
with open ("credentials.txt") as line:
line_1 = json.load(line)
for k,v in line_1.items():
router=(k,v)
try:
ssh = ConnectHandler(**router[1],device_type="cisco_ios",ip=ip_address)
ssh.enable()
except netmiko.ssh_exception.NetMikoAuthenticationException:
#incorrect credentials
continue
except netmiko.ssh_exception.NetMikoTimeoutException:
#oddly enough if it can log in but not able to authenticate to enable mode the ssh.enable() command does not give an authentication error
#but a time-out error instead
try:
ssh = ConnectHandler(username = router[1]['username'],password = router[1]['password'],device_type="cisco_ios", ip=ip_address)
except netmiko.ssh_exception.NetMikoTimeoutException:
# connection timed out (ssh not enabled on device, try telnet)
continue
except Exception:
continue
else:
output = ssh.send_command(ios_command)
ssh.disconnect()
if "at '^' marker." in output:
#trying to run a command that requires enble mode but not authenticated to enable mode
continue
return output
except Exception:
continue
else:
output = ssh.send_command(ios_command)
ssh.disconnect()
return output
output = connect_enable_silent(ip_address,ios_command)
for line in output.split('\n'):
print(line)
Credentials text is meant to store different credentials in case you are planning to call this function to access multiple devices and not all of them using the same credentials. It is in the format:
{"credentials_1":{"username":"username_1","password":"password_1","secret":"secret_1"},
"credentials_2":{"username":"username_2","password":"password_2","secret":"secret_2"},
"credentials_3": {"username": "username_3", "password": "password_3"}
}
The exceptions can be changed to do different things, in my case i just needed it to not return an error and continue trying the next set, which is why most exceptions are silenced.

Remote executing of program via xterm run using paramiko python ssh library

Flow of the program is:
Connect to OpenSSH server on Linux machine using Paramiko library
Open X11 session
Run xterm executable
Run some other program (e.g. Firefox) by typing executable name in the terminal and running it.
I would be grateful if someone can explain how to cause some executable to run in a terminal which was open by using the following code and provide sample source code (source):
import select
import sys
import paramiko
import Xlib.support.connect as xlib_connect
import os
import socket
import subprocess
# run xming
XmingProc = subprocess.Popen("C:/Program Files (x86)/Xming/Xming.exe :0 -clipboard -multiwindow")
ssh_client = paramiko.SSHClient()
ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh_client.connect(SSHServerIP, SSHServerPort, username=user, password=pwd)
transport = ssh_client.get_transport()
channelOppositeEdges = {}
local_x11_display = xlib_connect.get_display(os.environ['DISPLAY'])
inputSockets = []
def x11_handler(channel, (src_addr, src_port)):
local_x11_socket = xlib_connect.get_socket(*local_x11_display[:3])
inputSockets.append(local_x11_socket)
inputSockets.append(channel)
channelOppositeEdges[local_x11_socket.fileno()] = channel
channelOppositeEdges[channel.fileno()] = local_x11_socket
transport._queue_incoming_channel(channel)
session = transport.open_session()
inputSockets.append(session)
session.request_x11(handler = x11_handler)
session.exec_command('xterm')
transport.accept()
while not session.exit_status_ready():
readable, writable, exceptional = select.select(inputSockets,[],[])
if len(transport.server_accepts) > 0:
transport.accept()
for sock in readable:
if sock is session:
while session.recv_ready():
sys.stdout.write(session.recv(4096))
while session.recv_stderr_ready():
sys.stderr.write(session.recv_stderr(4096))
else:
try:
data = sock.recv(4096)
counterPartSocket = channelOppositeEdges[sock.fileno()]
counterPartSocket.sendall(data)
except socket.error:
inputSockets.remove(sock)
inputSockets.remove(counterPartSocket)
del channelOppositeEdges[sock.fileno()]
del channelOppositeEdges[counterPartSocket.fileno()]
sock.close()
counterPartSocket.close()
print 'Exit status:', session.recv_exit_status()
while session.recv_ready():
sys.stdout.write(session.recv(4096))
while session.recv_stderr_ready():
sys.stdout.write(session.recv_stderr(4096))
session.close()
XmingProc.terminate()
XmingProc.wait()
I was thinking about running the program in child thread, while the thread running the xterm is waiting for the child to terminate.
Well, this is a bit of a hack, but hey.
What you can do on the remote end is the following: Inside the xterm, you run netcat, listen to any data coming in on some port, and pipe whatever you get into bash. It's not quite the same as typing it into xterm direclty, but it's almost as good as typing it into bash directly, so I hope it'll get you a bit closer to your goal. If you really want to interact with xterm directly, you might want to read this.
For example:
terminal 1:
% nc -l 3333 | bash
terminal 2 (type echo hi here):
% nc localhost 3333
echo hi
Now you should see hi pop out of the first terminal. Now try it with xterm&. It worked for me.
Here's how you can automate this in Python. You may want to add some code that enables the server to tell the client when it's ready, rather than using the silly time.sleeps.
import select
import sys
import paramiko
import Xlib.support.connect as xlib_connect
import os
import socket
import subprocess
# for connecting to netcat running remotely
from multiprocessing import Process
import time
# data
import getpass
SSHServerPort=22
SSHServerIP = "localhost"
# get username/password interactively, or use some other method..
user = getpass.getuser()
pwd = getpass.getpass("enter pw for '" + user + "': ")
NETCAT_PORT = 3333
FIREFOX_CMD="/path/to/firefox &"
#FIREFOX_CMD="xclock&"#or this :)
def run_stuff_in_xterm():
time.sleep(5)
s = socket.socket(socket.AF_INET6 if ":" in SSHServerIP else socket.AF_INET, socket.SOCK_STREAM)
s.connect((SSHServerIP, NETCAT_PORT))
s.send("echo \"Hello there! Are you watching?\"\n")
s.send(FIREFOX_CMD + "\n")
time.sleep(30)
s.send("echo bye bye\n")
time.sleep(2)
s.close()
# run xming
XmingProc = subprocess.Popen("C:/Program Files (x86)/Xming/Xming.exe :0 -clipboard -multiwindow")
ssh_client = paramiko.SSHClient()
ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh_client.connect(SSHServerIP, SSHServerPort, username=user, password=pwd)
transport = ssh_client.get_transport()
channelOppositeEdges = {}
local_x11_display = xlib_connect.get_display(os.environ['DISPLAY'])
inputSockets = []
def x11_handler(channel, (src_addr, src_port)):
local_x11_socket = xlib_connect.get_socket(*local_x11_display[:3])
inputSockets.append(local_x11_socket)
inputSockets.append(channel)
channelOppositeEdges[local_x11_socket.fileno()] = channel
channelOppositeEdges[channel.fileno()] = local_x11_socket
transport._queue_incoming_channel(channel)
session = transport.open_session()
inputSockets.append(session)
session.request_x11(handler = x11_handler)
session.exec_command("xterm -e \"nc -l 0.0.0.0 %d | /bin/bash\"" % NETCAT_PORT)
p = Process(target=run_stuff_in_xterm)
transport.accept()
p.start()
while not session.exit_status_ready():
readable, writable, exceptional = select.select(inputSockets,[],[])
if len(transport.server_accepts) > 0:
transport.accept()
for sock in readable:
if sock is session:
while session.recv_ready():
sys.stdout.write(session.recv(4096))
while session.recv_stderr_ready():
sys.stderr.write(session.recv_stderr(4096))
else:
try:
data = sock.recv(4096)
counterPartSocket = channelOppositeEdges[sock.fileno()]
counterPartSocket.sendall(data)
except socket.error:
inputSockets.remove(sock)
inputSockets.remove(counterPartSocket)
del channelOppositeEdges[sock.fileno()]
del channelOppositeEdges[counterPartSocket.fileno()]
sock.close()
counterPartSocket.close()
p.join()
print 'Exit status:', session.recv_exit_status()
while session.recv_ready():
sys.stdout.write(session.recv(4096))
while session.recv_stderr_ready():
sys.stdout.write(session.recv_stderr(4096))
session.close()
XmingProc.terminate()
XmingProc.wait()
I tested this on a Mac, so I commented out the XmingProc bits and used /Applications/Firefox.app/Contents/MacOS/firefox as FIREFOX_CMD (and xclock).
The above isn't exactly a secure setup, as anyone connecting to the port at the right time could run arbitrary code on your remote server, but it sounds like you're planning to use this for testing purposes anyway. If you want to improve the security, you could make netcat bind to 127.0.0.1 rather than 0.0.0.0, setup an ssh tunnel (run ssh -L3333:localhost:3333 username#remote-host.com to tunnel all traffic received locally on port 3333 to remote-host.com:3333), and let Python connect to ("localhost", 3333).
Now you can combine this with selenium for browser automation:
Follow the instructions from this page, i.e. download the selenium standalone server jar file, put it into /path/to/some/place (on the server), and pip install -U selenium (again, on the server).
Next, put the following code into selenium-example.py in /path/to/some/place:
#!/usr/bin/env python
from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException
from selenium.webdriver.common.keys import Keys
import time
browser = webdriver.Firefox() # Get local session of firefox
browser.get("http://www.yahoo.com") # Load page
assert "Yahoo" in browser.title
elem = browser.find_element_by_name("p") # Find the query box
elem.send_keys("seleniumhq" + Keys.RETURN)
time.sleep(0.2) # Let the page load, will be added to the API
try:
browser.find_element_by_xpath("//a[contains(#href,'http://docs.seleniumhq.org')]")
except NoSuchElementException:
assert 0, "can't find seleniumhq"
browser.close()
and change the firefox command:
FIREFOX_CMD="cd /path/to/some/place && python selenium-example.py"
And watch firefox do a Yahoo search. You might also want to increase the time.sleep.
If you want to run more programs, you can do things like this before or after running firefox:
# start up xclock, wait for some time to pass, kill it.
s.send("xclock&\n")
time.sleep(1)
s.send("XCLOCK_PID=$!\n") # stash away the process id (into a bash variable)
time.sleep(30)
s.send("echo \"killing $XCLOCK_PID\"\n")
s.send("kill $XCLOCK_PID\n\n")
time.sleep(5)
If you want to do perform general X11 application control, I think you might need to write similar "driver applications", albeit using different libraries. You might want search for "x11 send {mouse|keyboard} events" to find more general approaches. That brings up these questions, but I'm sure there's lots more.
If the remote end isn't responding instantaneously, you might want to sniff your network traffic in Wireshark, and check whether or not TCP is batching up the data, rather than sending it line by line (the \n seems to help here, but I guess there's no guarantee). If this is the case, you might be out of luck, but nothing is impossible. I hope you don't need to go that far though ;-)
One more note: if you need to communicate with CLI programs' STDIN/STDOUT, you might want to look at expect scripting (e.g. using pexpect, or for simple cases you might be able to use subprocess.Popen.communicate](http://docs.python.org/2/library/subprocess.html#subprocess.Popen.communicate)).

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