Networking issues you need help with.

This has been driving me nuts for 2 days and MS won't let me open a ticket because the environment has servers running on Virtual Box (don't ask).

Here's what's going on:

I have a client running a lot of old hardware. I mean, a lot. But they never had connectivity issues until recently. Basically what's happening is that every client machine loses network and internet connectivity for a few seconds. This is intermittent. It happens to some machines at the same time, others at different times. It's really weird.

For the most part, they're connecting mainly to their DC which has a lot of shared drives and their active sync drives on it. That machine isn't losing connection (that I can tell. I could remote into it when they had an extended downtime yesterday and couldn't connect internally). So it sounds like an issue with the switch then, right? Well, maybe. I restarted the switch and the problems persisted.

I did find a loopback on their 2 switches, though. That was removed towards the end of business hours yesterday. The connectivity problems continued until I restarted their DC about an hour ago. There has been no complaints since.

Well, a few people tell me they had issues following the restart but I'm questioning their perception of time. I'm still trying to run this down to be sure.

The DC is Server 2003 SP2 and most of the clients are XP SP2 (I know) but there are a few 7 SP 1 machines in there having the same issue.

Could the problems caused by the loopback linger after it was removed or could this be something else entirely? Let's assume their 2 switches are good as I'll be testing those on my own.

Physical NIC might be flaky... physical cabling might be flaky... cheap enough to isolate and remove from the equation.

Checked for an IP conflict?

Grr so getting everything up and running, now my router appears to be busted.

1) Have a d-link DI 524. flashed bios at least once.
2) was working fine for the last 2 years
3) recently installed a powerline networking thing into one of the LAN ports that was working fine.

So this morning, my wife noticed her laptop switch to wireless mode, I notice my connection slow to a crawl then die. I try logging into the router gateway and chrome hangs on "Resolving Proxy".

I do the standard reboot everything, and it looks like it works, so I think im in the clear, but 2 minutes later everything drops again. Ipconfig shows me connected but I can't log onto router. Ipconfig release renew also not working on LAN. Strangely, wireless appears to be working (on iPad now).

I thought maybe a conflict arose from the powerline thing even though it worked fine, so unplugged that and still no dice.

Could my router lan ports have just all died at once? The fact that my wireless is working on the same router seems weird to me. Any thoughts before I buy a replacement?

Oh, hey, I'm still waiting on final confirmation for mine but it appears taking out the 2 (2!!!!!!!!!) loopbacks we found on the network and resetting the POS server running their DC VM did the trick. I'll find out in a few days.

In the meantime, I'll change the thread title so we can all wallow in the misery that network problems bring about.

Heh thanks for changing topic... I feel so nervous starting new ones. Figured I'd just hijack yours.

Seems like a hardware issue for me.... Te date/time on the router read jun 1, 2011... Hasn't set to current time and been running for the last 2 hours.

Could my router lan ports have just all died at once?

Sure, that can happen. Those smaller consumer router/switches usually run the four LAN ports as a switch, driven by a single specialized chip that does switching. If that chip fails for some reason, you can easily lose all the LAN ports at once. It's also pretty common for the WAN port to be on a different physical chip, which would also match your symptom of wireless access working, but wired access failing. Those little routers can be pretty flaky, over longer periods of time, because they tend to have only passive ventilation, and often are stuck into closets or other small airspaces without much air circulation, so chips getting cooked is not that uncommon.

Do you have another router, even an old and crummy one, that you can test with? And just to be sure that the cat didn't eat a cable or something, have you tried with a different cable? Your wife's machine also failing probably rules that out, but if it's easy and quick to swap cables, I'd suggest doing so.

Well I tried unplugging everything in the LAN ports and resetting one last time and it seems to be working. I still only have 1 thing plugged in as my wife has to do some work and I don't want to interrupt her. Once she's done I'll try plugging a few more things. Maybe there was something borked with with the DCHP handling and unplugging all connected PCs and resetting the router fixed it? Dunno.. making up guesses now.

Did you reset the router after you fixed the loopback issue? I'm just wondering if the switch might be holding onto old routing tables even though the routes have changed? Also, if the router has some open ports, try switching the DC to an unused port. I've had routers where only 1 or 2 ports went bad. You might have 1 or 2 on the way. I also had a router that I'm fairly certain took a lightning strike that would run fine right up until it just froze solid. (I could tell when this happened because every light was on whether the port was in use or not.) I'd power cycle it and it would run fine again for days until it froze up again. Had to replace that one.

Well we seem to have isolated the problem. For whatever reason, whenever my wife plugs her laptop into her docking station and through a cabled connection for some reason it blows up my router. If she's plugged directly in to her laptop, and outside of the dock, (or on wireless) everything works fine. Does that sound like anything someone has heard of? Docking station has been working fine for the last year or so, so not sure why it suddenly would screw up not only her network connection, but everyone else plugged into the router.