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View Full Version : SlimServer fixed my network!



Jon
2006-03-17, 22:13
I recently upgraded my network to Wireless-G, and ever since I've had networking problems between my laptop and my network; I could not see my file/print server from my laptop, could not access any network resources, etc. I had no problem accessing the internet - just LAN resources. My wife's laptop, however, had no problems. After weeks of trying to fix this, I was ready to give up.

I've also had problems with stuttering and hangs from one of my Squeezeboxes (two others worked fine), and tonight I decided to try to figure out the stuttering problem. After consulting the SlimServer wiki on wireless networking, I decided to check what channels my neighbor's routers were broadcasting on, and discovered about 6 networks (including mine) on Channel 6.

Changing my router to Channel 1 seems to have fixed the problems with my one Squeezebox - it is well behaved again. Strangely though, as soon as I made this change to my router, I could see all my network resources again from my laptop! I can't think of any reason why this would be ... though I am not going to look a gift-horse in the mouth ...

Michaelwagner
2006-03-18, 06:47
probably the interference from the neighbours was causing more than one problem.

Jon
2006-03-18, 07:30
probably the interference from the neighbours was causing more than one problem.
I figured as much ... I am just baffled as to how interference would have caused me problems accessing my lan server (which is hardwired to the router, btw)from my laptop but not cause problems accessing the internet. At any rate, I am thankful that my Squeezebox was having stuttering problems, else I would have had a much tougher time debugging this.

Michaelwagner
2006-03-18, 07:54
I figured as much ... I am just baffled as to how interference would have caused me problems accessing my lan server (which is hardwired to the router, btw)from my laptop but not cause problems accessing the internet. At any rate, I am thankful that my Squeezebox was having stuttering problems, else I would have had a much tougher time debugging this.

To speculate would be to imagine how the code might be written ...

I know that Network Neighbourhood is timer driven, that is, the actual support for Network Neighbourhood resides in another process (and often in another computer if you have a decent sized network, like a workgroup). So when you open Network Neighbourhood in explorer, all that happens is a request is fired off to the other guy process (whereever it is), and a timer is started. After some period of time, looks like 30 seconds to me, if no results come back, it says "no resources available". So on a network that's dead, it won't hang forever. On a network that's marginal (and I have some), sometimes you get some of the resources, sometimes you don't. Try it twice in a row, you can get different results.

I guess you'd have to say it isn't a very robust implementation.

The internet doesn't go through this path, so your results will vary.

Different versions of windows have different timeout periods, are more and less patient, etc. So that might explain why your wife's laptop had different results.

It's actually more complex than that (if you want the whole gory story - otherwise, let your eyes glaze over).

This "feature" is implemented by a service called the "computer browser service". It exists only on one computer in any group of computers. Any computer implementing "file and print sharing" can be the browser server. But there's a hierarchy. If there are 2 qualified computers, they will discover each other and play paper, scissors, stone for who gets to be the browser server. The guy who wins is the guy running the most up to date version of windows (that's a simplification, but it'll do). If you have a windows XP laptop who is sharing and goes regularly on and off the network, there will be times, when he leaves, when no one is the browser server, other times when 2 people are (briefly) the browser server, etc. Mayhem is the usual result.

And, of course, all lan resources like printers and disks, are discovered using this service.

So you can see if something destroys (even sporadically) network connectivity, you can have 0, 1, or 2 browser servers. In the case of 2, they can even have different ideas of what the network topology is (because neither can see the whole network, else they'd see each other and one would shut itself down).

In amongst the gaping holes in this scheme, there's plenty of place to believe that a somewhat broken network could support internet access (which bypasses this whole morass) just fine and yet break access to local disks and printers.

HTH

Jon
2006-03-18, 08:03
On a network that's marginal (and I have some), sometimes you get some of the resources, sometimes you don't. Try it twice in a row, you can get different results.HTH

Thank you ... this explains a lot. My ability to see the lan server resources through Network Neighborhood was sporatic ... sometimes the server, or a lan printer, would show up for brief moments and then dissapear again, a very frustrating situation! I believe that your description is what was actually occuring on my network, and have a better understanding now of why interference was likely the culprit. Thanks!

Michaelwagner
2006-03-18, 08:09
I realized, after I wrote all that from memory, how sad my life has become that I can recite all that from memory and yet can't recall the errand my girlfriend asked me to do yesterday ....

That is considerably more information than any user would ever want to know about such a trivial service, and yet, at the same time, considerably less information than you need to know in order to debug it with a packet sniffer (as I had to do once or twice).

I found that my workplace network became considerably more reliable when I could control which computer became the browse server, and left it on all the time. At that point, my difficulties (mostly) went away and I stopped the packet sniffing nonsense, since for my purposes the problem was solved.

I'm sure there's more to learn in that situation, but I had an actual job to do running my business, so I left it there (I'm my own IT guy only because we're strapped for staff).

Jon
2006-03-19, 20:32
I realized, after I wrote all that from memory, how sad my life has become that I can recite all that from memory and yet can't recall the errand my girlfriend asked me to do yesterday ....

Understandable ... the ramifications of networking issues are immediate and take lots of energy to resolve, so they get burned into your brain cells, while the ramifications of forgetting a couple of errands are deferred and (hopefully!) short-lived ...

At least, this is what I keep telling myself ...

Michaelwagner
2006-03-19, 21:36
the ramifications of forgetting a couple of errands are deferred and (hopefully!) short-lived ...

At least, this is what I keep telling myself ...
You must be single. :-)

Jon
2006-03-20, 15:38
You must be single. :-)

Or maybe I just have a forgiving wife ...