Ping function not working as expected.

[suthers]

Hi All,

My question relates to the behavior of the Ping function under certain conditions.

The code for testing this is:

$PingResult = Ping("192.168.1.2")
MsgBox (0,"Ping Test", "Ping Return Value = " & $PingResult & @CRLF & "@Error Value = " & @error)

The IP address above is our local Exchange server.  

If all is good, it outputs return value of 1 (ms) and @Error of 0 (no error)

If I unplug the network cable, it outputs return value of 0 (ms) and @Error of 2 (Host Unreachable)

All OK so far!  

However, if I clean reboot the machine with the network cable disconnected, it gives a return value of 1 (ms) and @Error value of 0

It's driving me batty, as there is no way to distinguish this result from the result returned when all is well and the server response time is 1ms.  

According the help file on the Ping command I should be testing the return value, and if it is > 0 a successful Ping was obtained - but in the clean reboot situation it is returning a value of 1 when the computer does not even have a valid network connection!

If I use the good-old Windows Ping command after the clean reboot, it correctly reports that it cannot send the ping request.

Is this a bug in the ping command?

Info for replicating the situation:

You must use a local IP address, not something requiring DNS resolution like myserver.local.  

Machine: Windows 7 Pro SP1 32 bit fully patched

AutoIT: V3.3.8.1

Thanks very much :-)

Bill

[wisem2540]

Personally, I would use Run(Ping) to call the windows one.  That is how I have always done it.

[wisem2540]

I actually just had to use this again...

Here you go

If RunWait("ping.exe -n 1 " & 127.0.0.1, "", @SW_HIDE) == 0 Then; success
;Do successful
else
;not successful
endif

[suthers]

Thanks very much for that suggestion for a work-around.  Will try that today.

I was hoping we could get the native AutoIT function fixed, but no-one seems to be posting in that regard.

[computergroove]

Perhaps the network card drivers need time to initialize when windows starts. Try waiting for a minute after the icons appear on the desktop and report back on the results. I run into this kind of thing all the time.

[suthers]

OK - will do.  I can't reboot my machine at present as it's running a long connectivity monitoring task for me, but will post back when I do.  I'm pretty sure I have already left it quite long (>10 minutes) times and it's still doing it, but will confirm definitely with a specific test.

[computergroove]

You say the program works when you run it but fails to work correctly after a reboot. What do you do to get it to work again after a reboot?

[suthers]

No, sorry, some misunderstanding there.  The only condition under which it fails is if the computer is rebooted with the network cable unplugged.  The issue is fixed as soon as a valid network is connected, or if the computer is rebooted with the cable in place.

[computergroove]

Try pinging google

While 1
$var = Ping("www.google.com")

If not @error Then
;Your Script Here
Else
Sleep(1000)
EndIf
WEnd

[suthers]

Nice try, but no luck.  The script is testing mostly internal addresses, and often (due to our internet arrangements) the internet is inaccessible but the internal addresses are.  To kill the script based on loss of Google or DNS isn't an option.

[computergroove]

Do you get a reply if the cable is unplugged and you ping 127.0.0.1? If not then replace google with 127.0.0.1. I understand that there seems to be a bug in the internal Ping function within Autoit.

[suthers]

Thanks so much for all your help on this computergroove.

Yes, I do get a reply from 127.0.0.1 when no network is available - identical to the response from other internal network addresses.  Drat.  That was a good idea :-) 

I also tested the 'wait for everything to initialize' idea - no luck there either. No matter how long you wait the situation does not change. Looks like the only option at present is to use the Windows ping fuction via RunWait() as you suggested.

Is there a way to track whether the developers intend and/or have completed fixing AutoIT's own ping function?

Edited August 8, 2014 by suthers

[computergroove]

You can submit a bug report. Read the active tickets before you submit anything - http://www.autoitscript.com/trac/autoit/report