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Ping not pinging, but dns is resolving..

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jsteph

Technical User
Oct 24, 2002
2,562
US
Hi,
In my win98se system, when I ping from command prompt, say,
Ping I get:

Pinging tek-tips.com [216.45.19.33] with 32 bytes of data
request timed out
, etc, etc

So, the dns is resolving the address, why isn't the ping returning? Could my ISP be forbidding pings?? I can connect via internet (I'm here now), but I'm curious about this.
Thanks,
--jsteph
 
If you've got no major connectivity issues, and can surf the web, then the most likely explanation is that the ISP is blocking pings. It's not rare for ISPs to do this.

<marc> i wonder what will happen if i press this...[pc][ul][li]please give feedback on what works / what doesn't[/li][li]need some help? how to get a better answer: faq581-3339[/li][/ul]
 
If not the ISP, I wouldn't blame tek-tips.com for dropping all ping attempts from the outside. By doing this they can cut down the chance of a Denial of Service attack or people using ping-scanners to probe for open ports.. My bet is that they have their firewall configured to drop all icmp packets unless specifically coming from a known ip address - like the guy on call who has to maintain the network ;-)

~CN~
 
Interestingly, all .com / .net addresses now resolve (irrelevant of validity) thanks to Verisign's change to their TLD DNS servers. There's something rotten in this here resolution...

More at:
and

<marc> i wonder what will happen if i press this...[pc][ul][li]please give feedback on what works / what doesn't[/li][li]need some help? how to get a better answer: faq581-3339[/li][/ul]
 
That is interesting and your right - this definately smells of something.. I think will turn out to be a bad move in the end.
 
I know for a fact that BT are at least blocking Pings and a host of other services for the time being. They list the current outbreak of worms as their reason.
 
In my case, it seems to be the ISP--I've tried pinging a few dozen common and not-so-common sites, and not one gives a ping reply, though they all get addresses resolved. But I imagine many of the larger and more vulnerable sites are blocking from their end also.
--jsteph
 
The blaster worm has causd alot of ISP's to start blocking pings. The reason is because the discovery process of the worm uses ICMP to search for other hosts. This can flood the network and create a denial of service type situation.

I wouldn't be surprised if that was the case for you.
 
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