PING results..explanation needed? 1

[molecul3]

Hi all,

I am having this frequent problem at my office. Today, when everyone in my office tries to access a site (e.g.

http://www.thesitename.com)

it won't work. When i try to access that same site without "

http://www",

it won't work either. But sometimes, i try to access that site with "www" it works and without "www" it doesn't. Note that I am talking about the same URL in all cases.

What could be causing this?? When i try to ping that site with "www" 1 or 2 out of 4 pings will time out but when i run ping again without "

http://www",

i will get successful replies on all attempts. I repeated this a few times and got the same results. When i return to my office tomorrow, everything works fine again, with and without the "www" i am able to access that site. This problem occurs occassionally and i would REALLY like to know what is the problem or how do i go about finding out what is causing the problem. Thanks everyone. Hope someone can help me out.

Regards,
George

 

[KiscoKid]

If you're getting 1 or 2 dropped pings out of 4, that tells me there is a fair bit of packet loss to that site or on your network. Is this the only site where you have intermittent connection problems? If so, it could be that site. If all browsing and pinging seems slow and intermittent, it could well be a local LAN issue or a problem with your connection into the ISP.

I wouldn't place too much emphasis on whether you can ping or can't ping the

http://www/non-www

site or not as the registered DNS servers may be resolving them to different addresses. For example, see what happens when I ping

http://www.novell.com

and novell.com. The resolved IP address are different and likely different devices:



C:\>ping

http://www.novell.com

Pinging

http://www.novell.com

[130.57.4.27] with 32 bytes of data:

Reply from 130.57.4.27: bytes=32 time=170ms TTL=45
Reply from 130.57.4.27: bytes=32 time=160ms TTL=45

Ping statistics for 130.57.4.27:
Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 160ms, Maximum = 170ms, Average = 165ms
Control-C
^C
C:\>ping novell.com

Pinging novell.com [130.57.4.70] with 32 bytes of data:

Reply from 130.57.4.70: bytes=32 time=161ms TTL=45
Reply from 130.57.4.70: bytes=32 time=160ms TTL=45

 

[molecul3]

Hi KiscoKid,

Thanks for the reply, for your information, i tried pinging both with

http://www and

without and they both reply with the same IP. I checked that. But the weird thing was that the dropped packets came when i ping one of them but not the other. Really trying to figure out what is wrong. But the problem only occurs once in a while and tends to annoy everyone as no one is able to figure out what is wrong. :?

 

[manarth]

i tried pinging both with

http://www and

without and they both reply with the same IP. I checked that.

ping only uses dns to resolve to an IP. the actual ping part of it is independant of dns resolution.

ignore this anomaly - unless you've got some really bizarre firewall rules allowing pings only with a matching dns lookup (to a

http://www host)

- it's just a coincidence.

try using traceroute instead of ping - you should get an indication of where your packets are failing.

malware can cause erratic dns resolution (although usually the dns resolves incorrectly all the time, not occasionally). i'd say malware probably isn't the issue here, but it never hurts to run a scan!

<marc>
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