使用 Paramiko 一次创建多个 SSH 连接

Question

下面的代码通过 SSH 在一台机器上运行 grep 并打印结果：

import sys, os, string
import paramiko

cmd = "grep -h 'king' /opt/data/horror_20100810*"

ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect('10.10.3.10', username='xy', password='xy')
stdin, stdout, stderr = ssh.exec_command(cmd)
stdin.write('xy\n')
stdin.flush()

print stdout.readlines()

如何同时 grep 五台机器（这样我就不会出现重大延迟），然后将所有内容放入五个变量中并将它们全部打印出来。

Answer 1

您需要将调用放入单独的线程（或进程，但这会太过分），这反过来又要求代码位于函数中（无论如何，这是一个好主意：模块顶部没有大量代码等级）。

例如：

import sys, os, string, threading
import paramiko

cmd = "grep -h 'king' /opt/data/horror_20100810*"

outlock = threading.Lock()

def workon(host):

    ssh = paramiko.SSHClient()
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    ssh.connect(host, username='xy', password='xy')
    stdin, stdout, stderr = ssh.exec_command(cmd)
    stdin.write('xy\n')
    stdin.flush()

    with outlock:
        print stdout.readlines()

def main():
    hosts = ['10.10.3.10', '10.10.4.12', '10.10.2.15', ] # etc
    threads = []
    for h in hosts:
        t = threading.Thread(target=workon, args=(h,))
        t.start()
        threads.append(t)
    for t in threads:
        t.join()

main()

如果您有超过五个主机，我建议使用“线程池”架构和工作单元队列。但是，对于只有五个，坚持“专用线程”模型会更简单（特别是因为标准库中没有线程池，所以您需要像 threadpool...或者您自己的许多微妙的自定义代码；-)。

Answer 2

就我而言，我必须在具有一个 ip 和端口的服务器上执行命令，完成后需要对其他 ip 和不同端口执行 sftp。条件是由于端口转发，在对另一个 ip 执行 sftp 时一个连接应该处于活动状态。

两个连接都可以单独工作，但是在组合两个连接时，第二个 sftp 连接无法工作。

Answer 3

#! /usr/bin/env python3
import sys, os, string, threading
try:
    import paramiko
    #import paramiko package
except:
    im = input("Paramiko module is missing. Do you want to install[Y/N]:")
    im = im.upper()
    if im == "Y":
        try:
            try:
                os.system("pip install paramiko")
            except:
                os.system("pip3 install paramiko")
        except:
            print("Please install paramiko package manually")
    else:
        print("Rerun and type 'y' to install")

#Running paramiko module with interactive password sending function
#this function helps to send password when sudo command is executed
def sudossh():
    host = "type host ip"
    port = 22
    username = "type username"
    password = "type password"
    try:
        ssh = paramiko.SSHClient()
        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh.connect(host, port, username, password)
        ssh.get_transport()
        #In this example we will run HTTP module on server in port 80
        command = "sudo su -c 'sudo python -m SimpleHTTPServer 80'"
        print(f"Running: {command}\n")
        stdin, stdout, stderr = ssh.exec_command(command=command,get_pty=True)
        stdin.write("password\n")
        print("sent password\n")
        print("HTTP service is running now\n")
        stdin.flush()
        if stderr.channel.recv_exit_status() != 0:
            print(f"Error: {stderr.readlines()}")
        else:
            print(f"Output: \n{stdout.readlines()}")
        ssh.close()
    except Exception as err:
        print(str(err));
        print("Thanks for using my application");

#Running another paramiko module with interactive password sending function
def grepverification():
    host = "type host ip"
    port = 22
    username = "type username"
    password = "type password"
    try:
        ssh = paramiko.SSHClient()
        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh.connect(host, port, username, password)
        ssh.get_transport()
        #Open new session and check port 80 status on server
        command = "sudo su -c 'netstat | grep 80'"
        print(f"Running: {command}\n")
        stdin, stdout, stderr = ssh.exec_command(command=command,get_pty=True)
        stdin.write("password\n")
        print("sent password\n")
        print("Connection is established. Check below output\n")
        stdin.flush()
        if stderr.channel.recv_exit_status() != 0:
            print(f"Error: {stderr.readlines()}")
        else:
            print(f"Output: \n{stdout.readlines()}")
        ssh.close()
    except Exception as err:
        print(str(err));
        print("Thanks for using my application");


def main():
    #Multithreading helps to run both at a same time. Useful for verification.
    # creating thread
    th1 = threading.Thread(target=sudossh)
    th2 = threading.Thread(target=grepverification)
    # starting thread 1
    th1.start()
    # starting thread 2
    th2.start()
    # wait until thread 1 is completely executed
    th1.join()
    # wait until thread 2 is completely executed
    th2.join()
    # both threads completely executed
    print("Completed!")
#you can use for loop to reduce lines but for understanding & smooth multithreading process will keep it as separate functions
#Comments are welcome. Thanks. Follow me on https://www.linkedin.com/in/dinesh-kumar-palanivelu-858441128/
#you need to change line - 23-26,36,51-54,64

if __name__=='__main__':
       main()