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#1724 - 09/06/06 04:41 PM Error in current round trip only
Anonymous
Unregistered


I think I figured this out after I began creating this post. I did try to figure it out prior to now.

I was confused by "Err" in the current round trip but not in any of the hops. Now I realize that the error is probably occuring in a hop that is invisible; that is, no (other) information is available. I would include an image of what I am encountering but I don't see a way to upload an image; I assume I need to upload elsewhere and link to it. I can do that if necessary but you probably understand what I mean.

I am using the free version of Ping Plotter. It looks very useful and I appreciate getting it for free. I get the impression that it has not been improved for a while and generally it does not need improvement. If however I now understand what I did not understand (as described above) then an improvement would be to show "Err" for the current time for a hop even if no other information is available for the hop.

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#1725 - 09/06/06 10:44 PM Re: Error in current round trip only
Pete Ness Offline



Registered: 08/30/99
Posts: 1106
Loc: Boise, Idaho
You can attach an image - just do it while previewing your post (you'll see a field where you can browse to an image file).

The ERR column means that a packet was lost - on a non-responding hop, you'll always get ERR's (no responses). On the final destination, if it's showing up but you occasionally get an ERR on the final destination, then that means you're losing packets - look back at prior hops for packet loss.

Post an image and we'll have a look to see if there's anything we can see from that.

- Pete

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#1726 - 09/07/06 01:28 AM Re: Error in current round trip only [Re: Pete Ness]
Anonymous
Unregistered


Actually I don't see a way to upload images to this forum's space, so I uploaded it to my site. See

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#1727 - 09/07/06 11:36 AM Re: Error in current round trip only
Pete Ness Offline



Registered: 08/30/99
Posts: 1106
Loc: Boise, Idaho
Thanks for the picture.

It looks like there's a TTL bug with this server - where it sets the TTL of the returning packet to match the TTL of the incoming one. This isn't too common these days, but does happen occasionally.

All those intermediate empty "hops" are not real - this is just because of the TTL bug.

This shouldn't happen on other servers, so I recommend using a different target to troubleshoot - that will make things a lot easier.

- Pete

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#1728 - 09/07/06 12:04 PM Re: Error in current round trip only [Re: Pete Ness]
Anonymous
Unregistered


Thank you.

Then it was worth asking about this one.

You probably know who rr.com is, the target here.

Have you written anything to help us decide what target to use if we want to determine if we are having a problem with our ISP? I think I have read that that was the initial motivation to write Ping Plotter but I did not see anything with advice about what target to use. Of course you can't be too specific but everything I have seen has been too general.

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#1729 - 09/07/06 12:08 PM Re: Error in current round trip only
Pete Ness Offline



Registered: 08/30/99
Posts: 1106
Loc: Boise, Idaho
Ideally, you want to trace to the server that is having problems. If you're playing an online game and having lag / latency problems, then you want to trace to that server. If you're using VoIP and having voice quality problems, you want to trace to your VoIP server. If you can't do that, then your next best choice is a server in the same network area as the server you're having problems with. Sometimes, this can be the web server for the providing company, but often it is not. The next best choice is a reliable internet server (any one) that you know works well - that way you can eliminate (or not) your ISP as the culprit. Since all your packets are going to use your ISP (that's what your ISP does), if you have reliability problems tracing to a known-good server, and that problem shows up at hop 1 or hop 2, then you know it's an ISP problem.

- Pete

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#1730 - 09/07/06 12:17 PM Re: Error in current round trip only [Re: Pete Ness]
Anonymous
Unregistered


Thank you.

I have gotten off-topic enough that I should continue in another thread or something like that.

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