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>>>Free Trial: Website and Network Monitoring
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12.06.05
Unixart:
Tracking Site Problems
 By
A.P. Lawrence
As some of you know, I have Foo-web.com
and some other sites on another web hosting site. Recently I noticed that I'd
frequently get locked up for thirty seconds or so while editing files on that
site.
I wasn't losing my internet connection, and I wouldn't get dropped off: I could
keep on typing and when the connection came back, the screen would catch up. These
were frequent enough to be quite annoying and worrisome.
My first thought was an intermittent network problem at foo-web.com, so on another
screen I set up a ping from that site to aplawrence.com. I used "ping -i 10 aplawrence.com"
and went back to typing in my other screen. After a few minutes, my typing stopped
responding, and the output from the ping also paused. But when typing resumed,
the ping output resumed and nothing showed as lost. The pings continued working
while my screens were paused, which means that there was no network problem.
Well, wait, that's not necessarily true. It may be able to talk to aplawrence.com,
but it's not talking to me. So I changed the ping to instead point at the router
in my home office. If that failed during a hang-up, that would mean some transient
routing problem between me and the foo-web.com site. If it didn't fail, it would
have to mean something else - though I can't think of anything right now.
Unfortunately, I have yet to determine anything. Ever since I started doing 10
second pings back top my home router, I've had no connection pauses. This could
be coincidence, but it could also mean that the regular ping is a heartbeat that
is keeping the connection steady - my testing is affecting the problem. That's
something you always have to watch out for in troubleshooting: anything you do
potentially affects the problem you are trying to observe.
So.. whatever this is, it apparently isn't as simple as it looks. I'll have to
keep testing..
*Originally published at APLawrence.com
About the Author:
A.P. Lawrence provides SCO Unix and Linux consulting services http://www.pcunix.com
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