问题
I'm looking to add some functionality to a batch file that I've been writing; essentially what happens is I dial up a VPN connection using openvpn and then continue to mount a network drive as well as many other things, what I'm looking to do is:
- Dial the connection via OpenVPN (which I have working fine)
- Ping a host on the other side of the VPN and don't continue through the batch file until this host is reachable.
Currently I've been using a sleep command of 20 seconds which works, but is not a very clean or intelligent way of going about it; I'd imagine I need some sort of loop to attempt to ping the host infinitely until it is reachable before continuing in the batch file. Any help would be greatly appreciated.
回答1:
from antoher thread on stackoverflow... credit to paxdiablo (find the original post here)
@setlocal enableextensions enabledelayedexpansion
@echo off
set ipaddr=%1
:loop
set state=down
for /f "tokens=5,7" %%a in ('ping -n 1 !ipaddr!') do (
if "x%%a"=="xReceived" if "x%%b"=="x1," set state=up
)
echo.Link is !state!
ping -n 6 127.0.0.1 >nul: 2>nul:
goto :loop
endlocal
This will give you enough ammo to use and solve your problem
回答2:
as already mentioned years ago, output of ping is language dependent, so it's not a good idea to rely on a string like Received. The preferred and most reliable method is searching for the string TTL=:
:loop
timeout 2
ping -n 1 %ipaddress% |find "TTL=" || goto :loop
echo Answer received.
|| works as "if previous command (find) wasn't successful, then"
(as for the timeout: never build a loop without some idle time to reduce CPU load)
回答3:
It works if You translate the "Received" string using the string that your language uses for the word Received (i.e. in Italian is Ricevuti).
来源：https://stackoverflow.com/questions/14637892/pause-a-batch-file-until-a-host-is-reachable-using-ping