Baffling wireless problems/Linksys/Mediacom

Long time lurker (many many years) first time poster and I'm counting on the great folks here to help out a long time Computer Geek (25 years)

This problem is baffling and I've spent 6 weeks troubleshooting it... so my description of the issue and what I've tried to do to solve it will be rather lengthy. My apologies in advance. :-D

About 6 weeks ago my internet connection began to drop randomly every few hours. No matter what I did it would stay down between 30 - 40 minutes, it will then reconnect and be sloooow for a few minutes, then go up and down several times and then, viola miraculously connected and zooming right along.

I have 5 computers in my house plus 3 - 4 that are here for repairs at any given time. (I work at home.) All have different OS's, browsers, Antivirus, etc. I have Mediacom internet, Linksys E1200 router & a Cisco R1000 range extender. Al have worked flawlessly until 6 weeks ago. I've had 5 streaming videos running on different computers plus a couple of gamers all at once with no issues prior to my mystery issue.

When the internet drops it will do so on 1 computer and the other 4+ will be fine. Or 2 and 3+ will be fine. Or 4 and 1 will be fine. You get the picture? It's never the same computer that will have the problem day to day, nor do ALL lose connection. The Dell is up and the HP is down. The next day the HP is up and the Dell and Toshiba are down. I never loss the internet entirely across the board. Some run wireless, some are plugged into the router.

I've done the usual simple stuff:
Release/Renew
Reset the adapter
Reboot
Reset range extender/router/cable modem

Nada. The problem computers will still not connect and the working ones still connect fine. After 30 - 40 minutes downtime they magically connect.

All drivers/OS's/AntiVirus'/browsers are fully up to date but with the variety of computers/software in place I think I can safely eliminate them from the problem.

Firmware has been updated on both the range extender & router. Both were purchased in 2012.

Mediacom has been called and they replaced the modem + some basic troubleshooting that was of course useless. I had to teach the tech who came to my house how to IP into the router... sigh.

I've reset MTU to 1365 (per google searching tons of forums )

I've turned off Upnp (per desperate google searching)

I've walked up and down the channels from 1 - 11 leaving each set for 24 hours. The problem reappears on each channel but otherwise the connection is stable and speedy when it is connected.

Removing the range extender from the mix makes no difference.

Assigning static IP's makes no difference.

Plugging a non-connecting wireless machine directly to the router makes no difference. Tho plugging straight into the cable modem works. However, I can't test to see if leaving it plugged into the modem directly will eventually result in a dropped connection as I can't leave all the other computers offline long enough to test. The cable modem has only one port. During a short 4 hour test the connection didn't drop.



Things I've noticed when the connection drops:

The computer(s) that lose the internet show 100% CPU usage for a few minutes just prior to dropping.

A Renew IP shows a DHCP timeout

I am usually (not always) unable to IP into either the Range extender or the router from a working computer. The working computer surfs fine and speedy but will not IP in. Once the dropped connections are back up I can IP into the router & range extender.

When I CAN IP into the router I will sometimes (not always) see 2 'no name' connections: 1 LAN and 1 wireless. If I can delete those I usually (but not always) regain connection on the down computers. This just may be a timing issue and they came back on their own.

Watching the link speed in Task Manager while the computer is regaining it's connection it bounces from 1mbps - 300 for a few minutes. Once it settles to 54, bing, it's connected and stable.

Watching the "Connect to a network' screen in windows it will cycle from Connecting... to Aquiring IP address .... to Connected with limited Access ... to Connected ... lather/rinse/repeat in rapid succession for a few minutes and then... stable.

During those few minutes I've checked the IP address being acquired and it climbs up the available numbers (gotta be quick to see it as it connects and disconnect so fast!) On average it will go thru 5 numbers before it settles on one it likes I suppose

Checking the router status I've noticed all computers with working IP's have had a new IP acquired for about the time the down computers have been down.

Lease time on the router is 4 days, for attached devices 1 day.

I have randomly IP'ed into the router when all computers are working and have rarely see a lease expires time of less than 23:xx:xx.

I have the router set for 50 connections. Looking at the DHCP clients table the IP's stay in the range of .129 - .149. I never see other numbers.

One conclusion was the router is renewing IP's every hour or so and chewing up all the available IP's. If that were so rebooting the router should be effective. Yes? Nope.

I increased the connections to 100... no luck there either.

And a couple obvious things: No cordless phones, no security systems, and no microwave interference.


I am so at my wits end at this point and am so hoping someone here will see the obvious solution I've missed. I've gone off on so many ideas and tangents in my troubleshooting and research I think I am finally blind from it all.

Please don't answer with 'buy a new router' ... One, as a geek I MUST SOLVE THE PUZZLE and two, if I was losing connection on every computer when this happens yes, I would, but really this is a mystery that needs to be solved.

If you've made it to the end of this tl/dr post my heartfelt thanks! Here's hoping there is magic here.

JC

 

Well it seems youve already done just about all the troubleshooting you can do. What i would do next is aquire another router to eliminate the possibility of it being a faulty router causing the problem. I know you didnt want to hear that but its the next logical thing to do.

And besides i must be the only one to get to the end of your post, or the only one to get to the end and have the audacity to still suggest another router :-D

Good Luck,
KJ

 

I agree with IrOnMaN that you have done a very thorough job in troubleshooting.
I will make some really left field suggestions below as they would be the only alternates I can think of after reading your post. (Started thinking about these last night.:-o)
I assume your wireless security and router security is up to snuff as you are pretty geeky.

Other possible steps for troubleshooting -
1) Leave 1 computer per day out of the mix rather than leaving only one connected and all others shut down.
2) Operating in Safe Mode with Networking one at a time.
3) Change DHCP range to start with a different number say .10 instead of .100 . Do you lose the first 30 IPs like you have seen starting at .100?
4) Check if a DHCP reservation has been made for whatever reason.
5) Do a DHCP reservation out of the DHCP range for all the comps and assign static IPs again to match the reservations.
6) Is the router on a surge protector or do you have flaky electrical power or recent storms to possibly cause an intermittent hardware fault in the router?

Good Luck.:major

 

Thanks for the replies guys!

Even for suggesting buy a new router.

1) I'm not quite sure I get what you mean here. I have 5 computers running at any given time here (Me, Hubby & Teenagers) Plus those odd 3+ that I'm repairing. During those rare times it's only me at home and I've just been on my computer I've had it drop. I can boot another computer in the house and it will connect just fine. Does that fit your scenario?
2) I had a family's 3 computers here for repair as they'd decided they would share a lovely virus with absolutely no protection. All three were in safe mode w/networking when an episode occurred. I don't remember off hand if 1 or 2 went down... but 1 definitely stayed connected.
3) I just did that after reading this... only time will tell
4) Although I didn't go into that much detail in the op I've run rings around DHCP reservations and assigning static IP's. Probably was tired after all that typing!
5) I have APC Smart UPS's for EVERYTHING... during summer storms here we can get brown-outs and since I'm responsible for client computers I can't take a power surge risk. However, I didn't experience any sort of power issue around the time this happened. That I know of And the APC's should handle that just dandy.

I do have some new info from experimenting today.

My neighbor has mediacom and a older linksys router WRT54g. The very same workhorse router that lasted me 5 years until it died... hence the new E1200. She leaves here network unsecur for 'the neighbor kids' ... gack!

I asked her permission this morning to connect 3 computer to her wireless. One was my personal laptop and 2 were here for repair. Same issue happened 6 hours later. 1 computer (one in for repair) lost connection and stayed down 30 minutes. The other 2 were connected and surfing fine. I also could not IP into her router during that 30 minutes. She has experienced an occasional outage but tells me she's rarely on her home computer so she might not see it like I do. She thought it was Mediacom going down as it's "notoriously bad in our area."

Umm... interesting. And... makes absolutely NO sense! It really should be a flakey router.

I'm beginning to doubt a new one will really be the answer now. I've always used linksys/cisco, and my range extender is linksys and while I would rather not buy both a new router and extender... I would entertain recommendations for another brand.

Thanks again for the ideas.

 

Greetings, Cryndalae...

I'm leaning towards agreeing with plodr, especially if lbmest's DHCP suggestions don't pan out. Coupled with your neighbor's symptoms this looks like a provider problem.

We had a somewhat similar issue recently with Bellsouth/AT&T - random dropouts affecting different users on a rural node. Turns out it was some obscure filter circuit board in a telephone switch causing the problem - the Bellsouth tech told me that one of their gurus figured it out by connecting data loggers on the phone frame itself. Weird.

Make some noise - demand satisfaction from Mediacom.

 

+1 on plodr's and Caliban's posts.

Yes on the 1) situation.

Any new construction, ISP upgrade work or other construction in area?
Extreme weather conditions - cold/wet etc.? Something that might have affected ISP cabling?

I'm out of suggestions.

Good Luck.:major

 

I have a feeling that I will have to bite the bullet and really push with Mediacom. While they did respond initially with a new modem, again the tech who brought it out was so unqualified he didn't even know how to IP into the router. By phone I haven't been able to get them to address this issue beyond 1st tier support. By the time I've finished explaining the problem, the things I've done to correct it and go through their scripted troubleshooting it's been 30+ minutes and I'm up and connected again. They say case closed. Or, call when it's down again. Lather/rinse/repeat. Sigh.

To their credit Mediacom is quite responsive, friendly and willing to take time to address my issue... they just don't have the skills to go even as far as I've gone to resolve this and the only time they get fussy is when I want to be bumped up the food chain.

plodr: I'll post there now. Might get something out of it.

Ibmest: We had severe outages in August while they were 're-cabling' this area for higher speed/better quality. They notified us in advance and we received a 30% discount that month for broadband. From Sept until 6 weeks ago the speed improved drastically from an average of 3-4 up/1-2 down to 7-10 up/4-5 down. I know... still crappy... but better. They didn't however replace any outside cabling on our property.

Speeds in the last six months are all over the map. Interestingly, as I write this, this computer is at the lower speed and my ancient desktop is testing at the higher speed. I think this computer my be on it's way to a connection drop? Umm...

We may yet solve this folks! Thanks for all you advice and wish me luck with the upcoming Mediacom phone battle!

 

Does an ISP problem really explain why some computers are working fine when others are down? You did say leaving a computer connected to the modem for 4 hours didnt drop. Maybe when the drop happens you can take one of the dropped computers and plug into the modem to see if it instantly works again. The router may not be bad but maybe there is some kind of configuration on it that the modem does not like. The only problem i see with Mediacom is they are apparently incapable of resolving your problem. Well maybe not completely incapable, im sure there is at least one person there that knows what they are doing like everywhere else.

 

Alrighty folks... had quite a marathon with Mediacom and here's the result.

After only 30 minutes I was able to get to 2nd tier support. \0/ Since everything was working at the time we talked he couldn't test a whole lot. But he spent quite a long running various tests on his end. Line signal was fine, speeds while on their low end of their 'promised' service were considered acceptable.... yada yada yada

He said I really should be getting 12-15/8-9 with the upgrade to our area... I NEVER see that. That led him to a idea that perhaps we are seeing a drastic drop in bandwidth which causes some computers to lose connection until I'm back up to a 'full pipe' (? weird way of putting that)

He made a few tweaks to the cable modem (I don't know what) and gave me his direct line to call when I have an episode so he can look further.

Unfortunately the next episode happened at 3:30am ... but it was different.

At first the computer was all of a sudden surfing like it was connected to a 300 baud modem for example: surfing to CNN produced a black and white test only screen with blue text links. Same story on a couple other sites until I lost the internet entirely.

However I still had a IP address and could IP into my router. That's new... new is good. :-D

I checked the DHCP clients list in the router and 'woke up' the 2 computers listed who had IP's. Both couldn't surf but could IP into the router.

I booted up another computer and it obtained an IP from the router but couldn't surf.

I connected to my neighbors wireless (see description of that in an earlier post) I did not get an IP and could not IP into her router. Interesting.

I rebooted the router and all computers could surf and they kept their previous IP's. Again, interesting.

Per Ibmest suggestion earlier I'd changed the starting IP to 120. All IP's assigned now stay between 159 - 179. Clue? Maybe.

About an hour ago ALL 5 computers that were on and surfing lost connection to the internet. Same as in the middle of the night: Sloooooooowed way down, couldn't surf, could IP into the router. This is new and again, new is good (Is it weird I think it's a good thing that ALL the computers lost their internet?)

So what did I do? Immediately rebooted the router and all were back up and surfing. All had their previous IP's as well.

So what did I forget to do? CALL MEDIACOM while the problem was occurring! Dang. I will have to wait for another episode and stop my autogeek pilot.

The tech made no changes to my router and only tweeked the cable modem. So I can't really tell you what may have caused the change. But I am happy that, at least for now, a reboot of the router gets me up and running and I can stop losing so much time when I have these episodes.

So? New thoughts with the new info? I believe this now brings me back to square one on troubleshooting. Yes?

Happy Friday to all!

 

Well glad to see some change. I prefer all computers get disconnected than random ones lol. I dont quite agree with what the tech said that about the drastic drop in bandwidth. if that was the case then all the computers would have had no internet at the same time.

Ok so if the starting ip is 120 why are they between 159-179.

Is it somehow getting ips from your modem and not your router?

im still leaning towards some configuration between the modem and router. possibly more so with the router but i dont know what restarting it does to make it work again.

All shots in the dark so your best bet is calling that guy when it happens again.