Tech: Router failures

Subject: RE: BS: Tech: Router failures
From: GUEST, Richard Bridge at London South Bank univers
Date: 13 Jan 10 - 09:01 AM

Thank you Simon - that is sounding quite likely

Subject: RE: BS: Tech: Router failures
From: Simon G
Date: 13 Jan 10 - 08:39 AM

SRS - routers connected to the internet aren't actually asked to do very much. The network connections on the LAN side will be rated at 100Mb/s and the switch will usually cope with all 4 connections running flat out - 400Mb/s.

In practice most of the traffic is heading to and from the internet which will be running at 4-20Mb/s a fraction of the capability of the LAN side of the router.

Routers do have to keep records of current connection out through them to the internet this table can overflow and crash the router. This would typically require 1,000s of connections to achieve. If this happens, either you are running something very special in terms of internet activity or malware on your computer is, the number of computers on the LAN won't be the reason.

A few years ago I had a customer running a 60 computer LAN through a bog standard home router on to the internet. The router never caused a problem. They have since moved to more expensive router, mainly to get load balancing across multiple internet connections, these fail every few months.

Simon

Subject: RE: BS: Tech: Router failures
From: Simon G
Date: 13 Jan 10 - 08:27 AM

Richard - Polyswitches do fail, they have a maximum voltage they can protect against and within the voltage range they are protecting from they are rated to switch at least 6,000 times and protect for 1,000 hours.

If it is polyswitches you would expect only the interface they are protecting to go down. So if they are on the phone line then only the internet/ADSL should disappear with the LAN functioning as normal, ie you can get to 192.168.0.1 from your computers. The LAN side may have one set of polyswitches for all the connections or a set per connection. If it was a wireless router (don't think it is) wireless would still work and wired wouldn't.

If you have Norton Internet Security on the computers, deinstall it and microwave the CD so your not tempted to reinstall.

Be careful testing that can reach 192.168.0.1 as Internet Explorer has allsorts of way it can get itself knotted up when the network on the computer is functioning correctly.

Testing the LAN.

If you get a light on the router socket you are connecting to then you have a basic network connection and it isn't the connection hardware.

If network icon up successfully in the bottom right corner then the router/switch it is are connected at the basic network level.

Open a command window (Start -> Run, type cmd and hit OK) type in ipconfig and hit Enter. The IP address on the interface should be in the range 192.168.0.2 - 192.168.0.254. If it is then the computer has made a network connection and used DHCP to get an address.

Type ping 192.168.0.1 then hit enter and you should get responses from the router. If so then there is nothing wrong with the network connection.

Type telnet 192.168.0.1 80 then hit enter and then enter until you get a response. If you get any text back with HTTP in it then you've made a connection to the web server on the router.

If you get to this point the network is working correctly, its Internet Explorer that is making it look as though it isn't.

Simon

Subject: RE: BS: Tech: Router failures
From: Richard Bridge
Date: 13 Jan 10 - 05:18 AM

I should have said I am running XP throughout at the moment although I sometimes have some Me and W98SE machines on the network.

I note that there does seem to be quite a high failure rate being experienced in general. Oddly my D-Link seems to ahve resurrected itself so I am happy at the moment.

TO deal with some of the other suggestions: -

Yes, I have had an electrician in (and he was computer savvy and knew about ethernet over power too) and he OK'd my mains all over the house.

Interestingly the ethernet over power works less well via the separate switch than straight into the modem-router-switch and that may point again to a problem with those devices.

Simon, do those polyswitches fail if overused? That sounds very like my issues.

Subject: RE: BS: Tech: Router failures
From: JohnInKansas
Date: 13 Jan 10 - 01:55 AM

I have had two DSL modem failures in the year+ since going to DSL, both replaced by my ISP.

I have had to do modem resets more frequently than I like, but it generally is tolerable. (Resetting the DSL modem works best if the connection is simplified to a single computer direct to the modem while the modem "rediscovers" the network.)

I've had a couple of incidents when I had to do a "page reset" for the modem, and a couple of similar ones requiring router page reconfigures. These require that you open the "url" where the settings are stored, and make a few unintelligible setting clicks that I generally let the support persons walk me through. (ISP support for the modem and manufacturer (Linksys) support for the router.)

All of the resets appear to have been the result of minor changes made by my ISP, most frequently when they've added or swapped servers at their end. The swaps should be transparent, but they have loaded me with a "default protocol" that doesn't work with my setup a couple of times.

Once you have multiple modems-routers-switches, the OS should add in necessary "bridges" in software to prevent looping within your multiple nets. WinXP did this efficiently in background, but Vista seems prone to screwing up. (Although I do have a slightly more complex net with Vista than I had with XP.) When you reboot, if it misidentifies any component of the network it may add new drivers/protocols. Competition between devices and redundant drivers/protocols can result in further misidentifications, with snowball effect on the network(s) setup. The end result is corruption of the data table(s) and everything turns to S**T. (USB connections appear most prone to this kind of corruption, but it probably applies to other device interfaces.)

If it's corruption in the OS data tables, Microsoft offers no useful answers, but the vaguely implied procedure is to disconnect everything, clear all the settings by disabling "everything network" in control panel, and then start at the "out end" by connecting the external modem to one computer, confirming the setup, then adding the first router between the same computer and the modem and confirming setup. Then proceed to add each device connection one-at-a-time, confirming each as you go, to let the OS rediscover the "clean" hookup and reconstruct the necessary data tables and supply the minimum necessary protocols.

Since this is a pretty tedjus process, you'll likely want to study whether it's a reasonable thing to do to address your symptoms. I can't make any real argument that there isn't another more obvious (and simpler) answer for what you're seeing.

John

Subject: RE: BS: Tech: Router failures
From: Stilly River Sage
Date: 12 Jan 10 - 11:28 PM

Simon, many of these home routers are only meant for four wired devices and maybe some wireless devices. Looks like nine wired (minimum). If several are pulling through the system at once, would they impact the modem?

SRS

Subject: RE: BS: Tech: Router failures
From: Rowan
Date: 12 Jan 10 - 10:28 PM

And, presumably, checking that your power circuits are all properly earthed?

Cheers, Rowan

Subject: RE: BS: Tech: Router failures
From: Simon G
Date: 12 Jan 10 - 08:24 PM

For sure you are not hitting the maximum capacity of the device, this is a really small network.

The fact you switch it off for a minute or so and it recovers points to devices called poly switches that are there to act as fuses in external connections to devices. They will cut the connection when there is too much current and only reset over a period of time with no power.

The likely culprit has to be the ethernet over power devices and may indicate your power circuits are not properly earthed.

I suggest plugging the ethernet over power device into a switch to isolate them from the router and see if your router survives longer.

Simon

Subject: RE: BS: Tech: Router failures
From: olddude
Date: 12 Jan 10 - 07:33 PM

joe
i get a year of of them myself, go with a DSL and you can have my switch if you want it. things will fly for you and it will last

Subject: RE: BS: Tech: Router failures
From: Joe Offer
Date: 12 Jan 10 - 07:30 PM

I have been having a lot of trouble with combined ADSL modem-routers, so I'm I'm thinking of using separate routers from now on.

I've always used separate routers on cable Internet installations because the local cable provider furnishes a cable modem, and even the cheap routers seem to last forever (and I usually leave them on 24/7).

I like the idea of a combined modem-router for ADSL, but the combined boxes seem to last just over a year (the usual length of the warranty). I think I'd better give separate ADSL modems a try.

-Joe (Northern California)-

Subject: RE: BS: Tech: Router failures
From: Richard Bridge
Date: 12 Jan 10 - 07:09 PM

I'm in the UK and experience has taught me to keep some spare modem-routers - the switches usually seem OK, so mains surge is unlikely or they would get it too, but they would be insulated from phone line surges by the modem-router.

I think I'll have a look at phone line surge protection.

Since all equipment seems to suffer equally I don't think it is an equipment MTBF issue, and because of the well ventilated location I don't think it's ordinary thermal runaway.

You have all helped to focus my thinking, thank you.

Subject: RE: BS: Tech: Router failures
From: The Fooles Troupe
Date: 12 Jan 10 - 06:41 PM

Normally, I would think that there are several possibilities (arranged in usual order of likelihood) for such regular failures.

1) Equipment quality
2) Thermal problems
3) Electrical surges/spikes

Subject: RE: BS: Tech: Router failures
From: The Fooles Troupe
Date: 12 Jan 10 - 06:32 PM

"whether voltage fluctuations could be coming down the phone line "

Having had much to do with Aussie phone systems, they USUALLY (and that USED to be the international way too) run on nominal 50V DC - but they can pick up induced voltages from other AC sources, as well as induced spikes from lightning strikes ANYWHERE within miles...

Subject: RE: BS: Tech: Router failures
From: The Fooles Troupe
Date: 12 Jan 10 - 06:29 PM

I WOULD be very suspicious of surges, especially with your IP over power stuff.

"surge protectors for phone lines"

Yep - I have several such power boards. They are often built in to some power boards here in Oz and some boards also have as well as the standard phone (memory may be going, so may say wrong things :) RJ12, but also a RJ45 - that's the similar connector, but has more connector pins - and they are the 'standard' for LAN cabling thing 6 pin vs 4 pin... If you haven't SEEN them locally, try looking online at the UK companies that make the power boards to see what they DO make in their full range, or go to some high end expensive place that focuses on the well heeled audiophile, they often stock the more eclectic power boards, such as the 'home theatre' boards, etc.

I have also seen locally gadgets that have only a single power plug AND the 'phone surge suppressors'.

Subject: RE: BS: Tech: Router failures
From: olddude
Date: 12 Jan 10 - 03:14 PM

That is a summit 48 port high speed switch, can't type today

Subject: RE: BS: Tech: Router failures
From: olddude
Date: 12 Jan 10 - 03:13 PM

Do you live in the states? I have a spare 48 network switch I can give you, super fast

Dan

Subject: RE: BS: Tech: Router failures
From: Richard Bridge
Date: 12 Jan 10 - 03:09 PM

I unplug, not just switch.

I am not on cable, but ADSL. ISPs tend to supply modem-only devices whereas I want a modem-router-switch, and those that do supply things for multiple access tend to do so with wireless devices which I will not countenance for security reasons.

The router is on my office desk, on the recommended feet, and close to a gap through which air to cool it rises. It is nowhere near sunshine and right now we have not got any in the UK. But I agree it looks like thermal failure.

One of the ones I have fried was a Linksys.

Local power supplies here are among the worst in the UK. I wondered whether voltage fluctuations could be coming down the phone line - phone lines feed power to the ringer devices in phones and for the mouthpiece and earpiece transducers. I also wondered if the ADSL filter should take care of that and whether there were surge protectors for phone lines too. I have never seen them.

My understanding of the switch system is that basic switches will address up to 256 IP addresses so I am not that inclined to believe that I need a bigger router. Commercial router-switches will be very expensive - they seem to start at about GBP 100 - and I will still need an ADSL modem - and it looks to me as if it is the modem-router interface that is the problem, since the network stays up even when internet access goes down. I suppose I could try a commercial multiway router, but then I am going to need either to deactivate the router in the modem-router or get a modem without a router in and that could be tricky apart from USP crap.


Hmm. I do not really want to eliminate the ethernet over power devices as I will then have to run cables all around my house, and it would mean leaving my lodger without internet access for the test duration - weeks or months - which might make him a bit ratty. But the argument is plausible if there are no other obvious suspects.

Subject: RE: BS: Tech: Router failures
From: Amos
Date: 12 Jan 10 - 02:01 PM

Instinct suggests that you try eliminating the IP over AC device as a test. I suspect you may get all kinds of oddball harmonics from it.

A

Subject: RE: BS: Tech: Router failures
From: McGrath of Harlow
Date: 12 Jan 10 - 01:52 PM

Jack the Sailor's point about using stuff supplied by the cable company makes sense - my experience with Virgin Media is that they are pretty good about replacing anything that stops doing the job. Of course you aren't using cable, but the same principle should apply.

Subject: RE: BS: Tech: Router failures
From: Stilly River Sage
Date: 12 Jan 10 - 01:27 PM

That sounds like an awful lot of stuff to be running off of that router. Maybe you need to go to a larger system device? You can't split the signal before the router because the cable company wants to address your router and probably frowns upon multiple routers. Unless you set up a business account, pay more, whatever. But a more durable system? I know I've seen some when poking around over at NewEgg.com.

SRS

Subject: RE: BS: Tech: Router failures
From: Donuel
Date: 12 Jan 10 - 01:18 PM

When I got hit by lightening our routers also fried.
Last month the wireless stopped working but was re initialiaed by the company and was fixed. Beyond that I'm like Sgt. Shultz.

Subject: RE: BS: Tech: Router failures
From: Rapparee
Date: 12 Jan 10 - 11:43 AM

I just replaced the router at home -- it lasted six years, and I only replaced it because it had to be rebooted every three days or so. So far the Linksys has worked fine.

Subject: RE: BS: Tech: Router failures
From: Jack the Sailor
Date: 12 Jan 10 - 11:29 AM

Our Modem is supplied by the cable company. When it fails they bring a new one. That has happened twice. We own our own routers which do seem to fail just after the one year warranties expire.

The only thing I would suggest to check which has not been mentioned is the location of your router. Is it in the sunlight or otherwise located where it might be overheating?

Subject: RE: BS: Tech: Router failures
From: artbrooks
Date: 12 Jan 10 - 09:54 AM

When you power down, do you unplug the box or just use the switch? I was told that the former was necessary.

Subject: RE: BS: Tech: Router failures
From: Richard Bridge
Date: 12 Jan 10 - 09:53 AM

1. Turning firewalls and antivirus off makes no difference, so it ain't that.
2. If it was DHCP allocation then disconnecting various bits would cure it, but once the routers have gone they won't even work with only one computer on.
3. Therefore it also can't be an ISP limitation (and anyway the ISP will only see the router, nott he items my side of it).
4. New expensive routers last no longer than cheap ebay ones. The fact that so many have gone makes it unlikely that the mtbf of cheap machines may be shorter than the more expensive ones.


All worth thinking about, but none likely to be the answer yet.

Subject: RE: BS: Tech: Router failures
From: Rapparee
Date: 12 Jan 10 - 09:46 AM

Since you're running on a private IP sequence, have you given each PC (and I suppose the Netbox) a separate IP address? If you're running DHCP I suggest you might try it.

Also, check with your ISP -- you might be running more than your public IP can handle.

Of course, buying the routers off of E-bay might be getting you some defective (or rather, more prone to failure) routers....

Subject: RE: BS: Tech: Router failures
From: McGrath of Harlow
Date: 12 Jan 10 - 09:45 AM

Could it be some kind of conflict between a firewall in the router and anti-virus stuff in the computer?

Subject: BS: Tech: Router failures
From: Richard Bridge
Date: 12 Jan 10 - 06:01 AM

I must have had ten modem-routers-switches fail in the last year. They seem to carry on working (usually) as router-switches so I generally have network but they cease to access the internet and the web interface ceases to be addressable (usually on the standard 192.168.0.1).

My system is pretty ordinary. ADSL to modem, the two downstairs computers on the built-in switch, ethernet link to a separate switch for the network storage and the two network printers, and ethernet link to a high-power "ethernet over power" gadget (Solwise) that connects to two more such gadgets upstairs, one for the computer in my library and one for my lodger who has another router in his room to connect his computer, his network storage, his X-box and his play-station.

All such things are on spike/surge protectors. My printers and monitors are not.

The failure pattern is the same every time. I put on a new modem-router-switch and once I have persuaded it to talk to the other switch everything is fine for a while. Then I start getting the modem-router-switch failing to give internet access (or even sometimes failing to give internet access to some computers) but working again if I power down and give it a minute or so presumably to cool down. Then I re-power it and away we go. Eventually the internet disappears completely, usually leaving (as I said) a network with no internet access and no access to the router's web interface.   

The latest to do it is a D-link - I'm currently running on my spare Netgear, and I have one more spare Netgear so it's nearly time to go back to E-bay and buy some more spares.

I'm open to suggestions what could be causing it.