Question

我有一个telnet路由器的脚本，如果它不能ping 8.8.8.8重启路由器，但我不希望它连续三次重启路由器。如果它在三次之后无法ping 8.8.8.8我希望它继续ping 8.8.8.8直到它再次恢复并重新开始。

import subprocess
output = subprocess.call('ping 8.8.8.8', shell=True)
while output == 0:
output = subprocess.call('ping 8.8.8.8', shell=True)
else:
import telnetlib
import datetime

now = datetime.datetime.now()

host = "912.168.1.1" # your router ip
username = "name" # the username
password = "password"
filename_prefix = "cisco-backup"

tn = telnetlib.Telnet(host)
tn.read_until("Username:")
tn.write(username+"\n")
tn.read_until("Password:")
tn.write(password+"\n")
tn.write("reload"+"\n")
tn.write("y"+"\n")
enter code here

我只是新手而且我不知道如何让else语句连续重复三次。

Answer 1

你缺少缩进词，所以我希望我的逻辑是正确的，无论如何，以下内容应该做你想要的。

在你的情况下，使用else语句几乎没有意义，因为这只会让你处于必须创建另一个while循环的位置。另一个修复是将output = subprocess.call...行移动到while循环的末尾，在路由器重置之后（如果你进入循环，如果没有响应则清除路由器，没有理由在重启之前再试一次）。

我添加了retries变量来跟踪路由器重置的次数，并将其作为条件添加到while循环中。如果重试次数超过3次，则循环将中断。

import subprocess
retries = 0
output = subprocess.call('ping 8.8.8.8', shell=True)
while (output == 0 and retries < 3):
    import telnetlib
    import datetime

    now = datetime.datetime.now()

    host = "912.168.1.1" # your router ip
    username = "name" # the username
    password = "password"
    filename_prefix = "cisco-backup"

    tn = telnetlib.Telnet(host)
    tn.read_until("Username:")
    tn.write(username+"\n")
    tn.read_until("Password:")
    tn.write(password+"\n")
    tn.write("reload"+"\n")
    tn.write("y"+"\n")
    output = subprocess.call('ping 8.8.8.8', shell=True)
    retries += 1

if (retries == 3):
    print ("Couldnt restore router")

Answer 2

你可以尝试这样做：

如果我理解正确，你要做的是制作一个脚本，将继续尝试ping 8.8.8.8，如果失败，它将重启路由器（最多3次），如果重新启动没有＆＃39;帮助脚本应该ping 8.8.8.8直到它成功。之后，脚本将重新开始。。

import subprocess
output = 0
while output == 0:
    output = subprocess.call('ping 8.8.8.8', shell=True)

    for i in xrange(3): #will restart the router until ping works OR at most 3 times

        if output == 0:  # if the ping succeeded don't restart the router
            break

        import telnetlib
        import datetime

        now = datetime.datetime.now()

        host = "912.168.1.1" # your router ip
        username = "name" # the username
        password = "password"
        filename_prefix = "cisco-backup"

        tn = telnetlib.Telnet(host)
        tn.read_until("Username:")
        tn.write(username+"\n")
        tn.read_until("Password:")
        tn.write(password+"\n")
        tn.write("reload"+"\n")
        tn.write("y"+"\n")

        output = subprocess.call('ping 8.8.8.8', shell=True) #after restarting the router check the ping again

    #after the loop
    while output != 0: output = subprocess.call('ping 8.8.8.8', shell=True)  #will ping until the ping work

Python：如何让else语句运行x次？

2 个答案: