Python多个telnet会话

Question

我需要构建一个脚本来获取尽可能多主机的telnet输出，并将它们保存到每个主机的单独文件中。脚本应该作为守护进程运行。

目前，我有一个函数，它用telnetlib封装了为单个主机执行此操作的逻辑，但我不知道如何继续。我计划为每个主机打开一个进程（multiprocessing.Process），但我怀疑这将是一种资源浪费，它必须以更好的方式存在：）

def TelnetLogSaver(hostname,ip,filename):   
    # open files and telnet sessions
    f = open(filename,"a")
    tn = telnetlib.Telnet(ip,23,TIMEOUT)

    # login
    e = tn.read_until("Login: ")
    tn.write(USER+"\n")
    # and password
    e = tn.read_until("Password: ")
    tn.write(PASSWORD+"\n")

    # Connected. Start infinite loop to save messages log
    while True:
        e = tn.read_until(PROMPT,TIMEOUT)
        if e is not "":
            f.write(datetime.datetime.now().strftime("%Y-%m-%dT%H:%M:%S"))
            f.write(e)
            f.flush()

        # avoid session timeout
        tn.write("\n")
        e = tn.read_until(PROMPT

Answer 1

我相信下面的代码可以满足您的要求，我把您的原始代码做成了一种线程：

import threading
import telnetlib
import datetime
import sys
# Global Variable Declarations
TIMEOUT = 30
USER = "Noel"
PROMPT = "Noel"


class listener(threading.Thread):
    def __init__(self, filename, ip):
        # Have to make a call to the super classes' __init__ method
        super(listener, self).__init__()
        self.f = open(filename,"a")
        try:
            self.tn = telnetlib.Telnet(ip, 23, TIMEOUT)
        except:
            print "Bad Connection"
            sys.exit(0)

    def run(self):
        # login
        e = self.tn.read_until("Login: ")
        self.tn.write(USER+"\n")
        # and password
        e = self.tn.read_until("Password: ")
        self.tn.write(PASSWORD+"\n")
        while True:
            e = self.tn.read_until(PROMPT, TIMEOUT)
            if e is not "":
                self.f.write(datetime.datetime.now().strftime("%Y-%m-%dT%H:%M:%S"))
                self.f.write(e.strip())
                self.f.flush()

            # avoid session timeout
            self.tn.write("\n")


if __name__ == "__main__":
    # Things to listen to is a dictionary of hosts and files to output
    # to, to add more things to listen to just add an extra entry into
    # the things_to_listen_to in the format: host : outputfile
    things_to_listen_to = {"localhost" :"localhost_output.txt"}
    # Thread holder is going to hold all the threads we are going to start
    thread_holder = []
    for host, file in things_to_listen_to.iteritems():
        thread_holder.append(listener(file, host))
    for thread in thread_holder:
        thread.run()

希望这有帮助，如果你有任何问题更新你的问题或留下评论。