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ctrl-c doesn't reliably kill ping


I have been having this problem with "ping". If I "ping" a location that doesn't exist, then "ping" just hangs and cannot be killed via "kill -KILL [pid]".

A little digression, so you understand the background ... The workstation I am doing this from is connected to a Verizon router to their FIOS network. Now the reason I mention this is that the router's DNS (via DHCP to my workstation) is 192.168.1.1, which I presume is forwarded from the router upstream to Verizon's DNS caches. So if I type the URL http://something.that.doesnt.exist in my browser, rather than getting a Hostname Not Found error (at the name resolution level), it actually loads up a page saying "something.that.doesnt.exist" isn't found and then I have a Yahoo set of search results on things matching the broken hostname.

So all of this is normal ISP stuff: they actually resolve unknown addresses to their own website (which is 90.242.140.21).

Ok, ending the digression ....

Back to the problem, so when I type

$ ping some.unknown.host

according to "ping", the hostname resolves to 90.242.140.21 (as per the explanation above), but I cannot kill "ping". I tried "ping" with a limited packet size and count so, in theory, "ping" would die on its own after 10 packets, such as:

$ ping some.unknown.host 50 10

but it still hangs rather than timing out. If I ping to some actual IP address that is unresponsive (route-able to the last subnet, but dies on the floor at the end), then I can kill via ctrl-c. My only solution to the hanging "ping" is to kill the terminal window.

Any suggestions on:

- Why "ping" behaves this way?
- How to avoid this problem?

Thanks, in advance.

-FF

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Frank Farance, Farance Inc.    T: +1 212 486 4700   M: +1 917 751 2900
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