Slashdot Mirror
Why Do We Have To Restart Routers?
jaypaulw writes "I've owned a WRT54G, some cheap D-Link home Wi-Fi/firewall/routers, and now an Apple Airport Extreme (100/10 ethernet ports). In the context of the discussion about the worst uses of Windows — installation in places where an embedded device is superior — I've gotten to wondering why it's necessary to reboot these devices so frequently, like every few days. It seems like routers, purpose-built with an embedded OS, should be the most stable devices on my network."
You're doing it wrong.
US Robotics 8054 (USR8054). At least it has the decency to reset itself though throughout the day. Saves some manual labor I suppose.
It shouldn't be necessary to do that.
Usually, though, it would be either a problem in the firmware leading to instability or a change in routing, DNS, or DHCP assignments that the router can't handle live for some reason. It could also be possible that the firmware allows no changes at all to the running configuration, forcing a restart for any change made in an attempt at making it less hackable.
-1 raving lunatic; +6 subGenius... Things even out...
I base this on absolutely nothing, but my primary suspect is the cheapskate power supplies that these devices come with. However I've never cared enough to test it out.
Fast, Stable, Cheap - pick two.
I'm guessing what you actually need to do is reset the connection to your modem or release and renew DHCP, Every router I've used allows you to login to a web based configuration and do these things.
I have a pair of Apple Airport routers, and the only time they get rebooted is when I change settings and restart them. That happens whenever I want to let another computer use my network, about every couple of months.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
I got my Belkin router about 4 years ago it runs great I can get about 3-6 weeks uptime before I have to manually pull the power cord because it crashes.
Its still going good and strong though!
Bought a Buffalo router and flashed it with DD-WRT. The only time the thing reset was when the power went out. If you're restarting your router every few days, I'd suggest looking into your config for the problem.
P.P.S. I'm doing Science and I'm still alive.
TCP connection timeouts on some routers default to 3600 seconds or one hour. So, when you use some Bittorrent or such, opening lots of connections, your router keeps these connections (even after disconnection) in its memory for up to an hour. It fills up and your router grinds to a halt, opening connections very slowly.
There's other timeouts too, but I'm not sure exactly what they do. Firmware like HyperWRT lets you change these timeouts to something much shorter, like 90 seconds, which typically prevents lock-ups like that.
(I'm actually not 100% sure that this is the sole cause for router lock-ups)
Not to be a dick, but I use a wrt54g with tomato firmware and it's about the most stable and powerful (QOS is great on it) router anywhere close to the consumer price range.
I never have to restart my DSL router or Vonage router either, and I've kept all this stuff up 24/7 often with heavy use for years at a time.
If you're restarting networking stuff all the time, perhaps you've misconfigured it...
The hardware on your router might be failing, power supply or whatever. I had the same problem with a DSL modem once, it eventually just outright died. The new one I bought (netgear DG834G) hasn't had to be reset once.
Gentlemen! You can't fight in here, this is the war room!
Most routers are cheap. (Apple's is overpriced-cheap; the point stands.) A bunch of them are free after rebates. Considering that, it's a wonder they keep running for more than 5 minutes. They come off the same assembly lines as those Norcent (who?) $15 DVD players.
You can buy reliable routers of course, from the C company, or the N company, or the J company, or a couple others. That's what corporations buy. What I wonder, though, is whether there's a middle ground: a "pro-sumer" router. Maybe somebody has got some suggestions.
If a client is able to cause a router to crash then there is something wrong with the router design.
And as you tread the halls of sanity, You feel so glad to be, Unable to go beyond. I have a message, From another time..
It's cheap, fast development... Not bothering to pay attention to correctness, not watching for memory leaks, etc., etc.
It shouldn't be that way, of course. I got an old K6-2 system, underclocked it to 100MHz, removed CPU fan and replaced the PSU fan with a very slow and quiet model to make a nearly-silent 8watt system. Then installed OpenBSD on a 32MB CF card (stripped of unnecessary binaries for size, but otherwise completely normal), and have been using that for years. It will run indefinitely, without a reboot. My record for uptime so far is 5 months, and it's only that short because of power outages, and I don't feel the need for a UPS for my router...
There's nothing about being "an embedded OS" that should make it any more or less stable.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
...the expectations of the user. Newsflash: when you buy cheap crap it is going to perform like cheap crap.
I want a new world. I think this one is broken.
I had a WRT54GX for years that never needed a reset, until I started using BitTorrent. Then its 4KB (?) connections table would fill up and the device would hang. Had to build an OpenBSD firewall to handle the many active and inactive connections you get with BT.
I've used some Zyxel router that needed restarting every few days until I found out the maximum amount of open connections and bandwidth it could take then it usually only crashed once a month.
Now I've got an old PII with a CF as HDD running monowall and maximum uptime so far is about two months. It would appear that the modem is more flaky than the router so I've restarted it needlessly a few times. I'm inclined to think it's hardware causing problems when the router crashes on its own. It's a bare motherbord sitting ontop a cabinet with four NIC's (I had an abundance of NIC's but no switch) and it gets a bit jangled from time to time in its exposed position. I'm amazed that it works at all.
Try to limit the amount of open connections if you're running bittorrent and maybe the bandwidth too. If that doesn't help you should probably build your own router. m0n0wall works for me and I've heard good things about IPCop.
I just use a cheap Pentium 2 running Windows XP with Internet Connection Sharing. Disabled the automatic updates and firewalled it properly over 18 months ago, and haven't had to touch the machine since.
If you have frequent power interruptions, aren't they rebooting your router frequently?
Beta sux! Join the Slashcott! http://hardware.slashdot.org/comments.pl?sid=4760465&cid=46173047
I'm running DD-WRT 23v2 on two Buffalo WHR-HP-54G routers, and I never have to reset them. However, I did have to update their configuration from the default settings in order to make them reliably stable. With the default settings, I would have to reset them occasionally. I changed the "maximum ports" from the default of 512 to 4096, and changed TCP and UDP timeouts from the default of 3600 seconds to 120 seconds. The reason for this (as stated in the DD-WRT help documentation) is that P2P apps often open many ports without closing them properly. These settings allow the router to handle that kind of usage much better.
I've got 5 WRT54G's running DD-WRT out in the desert in enclosures. They routinely operate in temperatures in excess of 110 degrees, and usually have a bunch of users on them.
Is that degree C, F or K?
http://michaelsmith.id.au
I had several "consumer" grade routers before finally finding the Dlink gamer lounge.
I've never been happier. I've had it for almost 2 years and I never have to reset it. The wireless always works, the gigabit is nice and the "Gamefuel" QOS is fairly effective.
The $100+ linksys routers aren't much improved over their $50 brethren, but the $100+ Dlink most certainly is.
crappy firmware. I flashed my WRT54G V4 with Tomato and haven't looked back. Also haven't had to reboot it in the past year or so that I've been using it, other than the occasional update. Tomato's developer obviously knows what he's doing: compared to the stock Linksys firmware he's lightyears ahead. And he's just one guy, you'd think a company with the resources of Linksys could do an even better job.
The higher the technology, the sharper that two-edged sword.
Ok, the router software - likely ripd, xorp, quagga or zebra for any domestic ADSL router - might crash, but the worst that will happen then is that you don't learn new routes. Since DSL providers don't tend to switch their internal IP addresses very often, that should not impact any existing subnet. It means tunnels can't be generated on-the-fly, it also means your next-door neighbor can't connect their LAN party to your wireless connection, but it shouldn't impact you in the slightest.
The next question, however, is how on Earth are you noticing the router needs rebooting? The kernel is quite capable of rebooting itself under many (but not all) soft lockups. Linux provides several such mechanisms for doing just that. A simple watchdog circuit, using a bistable circuit, a couple of capacitors, a relay and a trigger line that has to change state, could be added by a manufacturer for maybe a couple of dollars. It probably doesn't even need to be that complex.
When it does reboot, LinuxBIOS is under 3 seconds and I don't imagine OpenBIOS is that much slower. Intel's Tiano probably is, but it's open source so you can rip out anything that's useless. Therefore, recovery times should be barely detectable to an end user. (Most websites vary in download times by more than 3 seconds between visits. Unless you're playing Netrek or WoW at that precise moment, I seriously doubt you'll notice a 3 second outage.)
Finally, however, why isn't the router using carrier-grade software? Again, carrier-grade Linux exists, which should give you 5N uptimes in the worst possible case. Domestic routers are not worst-possible. Even data centers rarely get the kind of stress that could be expected to force an unrecoverable state. If your router is not overheating, has plenty of RAM, and needs rebooting more than once every other year, there is something seriously defective in the software or hardware.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
I have a similar setup on my Linksys WRT54GS. With the factory software it would lock up every other week -- wouldn't pass traffic and I couldn't log into it. Had to pull power to reset it. I loaded DD-WRT (23v2) and set it as you described and it has never failed to pass traffic, although every 3-4 months I can't access it from the Web GUI for some reason. I can still telnet into it though, so I just login from there and reset it.
I have a second WRT54GS (on it's own subnet providing open access to anyone in the area) and it's never locked me out of the GUI, although it doesn't pass nearly the traffic mine does.
I used to have a Blitzz router/AP that required rebooting every 3.5 days, regular as clockwork, regardless of traffic or number of connections. Pitched it in the dumpster when I got the second WRT54GS.
Beta sux! Join the Slashcott! http://hardware.slashdot.org/comments.pl?sid=4760465&cid=46173047
Cheap "embedded" devices like routers and NAS-es routinely have extremely bad hardware. The competition apparently is so fierce that cutting corners of everything, from basic motherboard-like functionality to network and disk controllers is ubiquitous.
I'm occasionally doing hardware reviews for a local IT magazine and it's unbelievable what you can actually buy today as a bona-fide good equipment even from "brand name" companies. CPUs are usually ARM or AMD GEODE (You think VIA is slow? Think again. - Not to say there isn't a place for slow CPUs, only that this isn't it.), network controllers are cheap Realtek's and I don't know what they use for disk controllers (probably parts of the CPUs "companion" chipset) but it sucks.
I've seen "gigabit" network controllers on NASes that actually negotiate gigabit speed, although they are connected to buses and CPUs that break a sweat even at 100Mbit/s speeds. NASes that accept 4 drives cannot service reads on even one drive at more than 15 MB/s - introducing RAID (especially RAID 5) into this setup slows things to a crawl.
Practically all of these devices use Linux, because it's free (as in beer). They usually (I'd say 90%) don't acknowledge or obey the GPL.
It's a sort-of reverse "best scenario" for Open systems (and Open source). The manufacturers have a choice between something like this:
The first choice is represented by "truly" embedded devices like ordinary small, unmanaged Ethernet switches (with which I have suprisingly good experience), but apparently it's too expensive to scale it to "smart" devices that have to support many features so everyone opts for the second one. You can (and this is verified!) build yourself a small managed router or a NAS device like the ones sold at every el-cheapo computer shop with the same cheap generic components, and the resulting device will be just as sucky.
Creating a router or a NAS just like the above but with "proper" hardware (a Duron 800 MHz based system will be excellent) won't even cost you significantly more, but will deliver orders of magnitude better performance.
-- Sig down
I run OpenWRT on a Linksys WRT54GS. Up 403 days right now.
That was my thought too when I saw this. If you have to reboot your router very often then you're doing it wrong.
We are heavy Internet users here at my home, especially since I work from home frequently and use VPN with the sending and recieving of large attachements, etc. I don't think I've ever *had* to reboot my WR54GT in the past year that I've had it.
Why DO you have to reboot your routers? Mine, including a WR54GT almost never require rebooting. Occasionally, after a power outage, it's necessary, but not very often. Maybe once or twice a year, and I live in Panama, where power interruptions come fairly frequently.
WTF? How did this end up +5 Informative?
The power interruptions are obviously regularly rebooting his equipment. Is it any wonder he doesn't need to reboot it himself?
Funny, I think everyone here has had to reboot their router to solve problems in the past. But, in typical slashdot fashion, 99.9 percent of the posts are people telling the author of the question that he is stupid, lacks intellectual ability, must be a high school drop out, or has some bastardized sexual persuasion that prevents his router from working.
As you say, it could be an unrelated issue that resetting the state machine fixes. In this case though I guess I superior device could do this on its own.
Did it ever occur to you that you never had a problem *because* of the power failures doing the rebooting for you?
it's simple, most router keep tcpip connections alive for 3600 sec or more (especially d-link one), so each time you establish a connection on a bittorrent client your router open a new one. After a few hours, sometimes a day or a few ones, it can become a problem very quickly as you might imagine. Just install dd-wrt or tomato and drop the timeout to 360sec, it'll do the job.
Stop buying shitty routers and you might have better experiences...I've used Netscreens (the old NS5/NS10s long since discontinued since Juniper bought them, but solid VPN/Firewall/Routers) for over 8 years - have easily had uptimes of over a year on some of them, and I've only ONCE needed to 'reboot' one (and that was after an especially bad lightning storm that nuked its UPS). It's not just the software/firmware/OS that leads to this (although it is a good part of it), but the actual physical components too.
Constant lockups, power cycles, and constantly losing DNS service... It was batshit insane.
Sometimes a firmware update can help. Not always but I do find it worthwhile updating the firmware and it has fixed problems for me in the past.. Having it on a UPS helps too; make sure you shield the data cables as well as the power cables. There are a few linksys units however that simply never seem to work reliably. My father has one. Just can't seem to hold a reliable connection for some reason. Mine on the other hand works damn near flawlessly.
I am like the previous poster. My Linksys WRT54G (Ver 3.0.3) has not been rebooted for a couple of years. I too didn't understand what the original poster was talking about, saying he reboots his router every couple of days. If you have a router that won't run more than a couple of days, I'd say you should get your money back. If enough people returned shoddy merchandise, the manufacturer would improve it (and might raise the price, but it would be worth it).
I have to agree, the current Linksys routers are LOUSY. I have a WRT54GS v6 that came with VxWorks and I've installed DD-WRT micro on. In both OSes it was crap -- Wi-Fi randomly dropping out, occasional crashes. It was especially bad on hot days and during heavy network traffic.
Apparently the Broadcom chip inside it was overheating. I ticky-tackied a PC fan to the table next to the router and powered it with a GameCube power brick (12v DC). The problem went away almost entirely, leaving me with a reliable but somewhat noisy router.
Later, I opened the router and placed an old heatsink off a Pentium on the offending chip (run it a while, see which one is hot), and used a piece of plastic wedged into the router's shell to press the heatsink down on the chip. The heatsink had some of that heat-conductive foam glue stuff some OEMs stick it to the CPU with on the bottom. Now (almost a year later) I have no fan next to it and it hasn't crashed or dropped the network yet.
I'm still stuck in the wimpy v6 flash and RAM though...
http://www.southparkzone.com/episodes/1206/Over-Logging.html
I fear the Y2038 bug
If you don't like the responses, maybe you should be browsing at +4 or +5?
There are many serious responses to this question that have already been posted. The good ones seem to cluster around the power issue. Which power supply sounds more reliable? A PC transformer is 3 pounds and $30-$70, a router transformer is 3 ounces and $3. Many slashdotters are software people, so the usual strategies of "blame the OS" or "blame the user" might be employed. The problem probably amounts to a hardware inadequacy.
I would never use a router without plugging it into the cheapest UPS I can find. Voltage fluctuates. The refrigerator compressor kicks on and the cheap Linksys transformer hiccups.
I've purchased many different versions of Linksys (some old, some new and crippled), Buffalo, Netgear, etc. They ALL go dead after a certain period of time if plugged directly into the wall. The WRT54G 1.1 transformer is physically larger than the 5.0 version. It probably burns more electricity, but it seems to be fairly reliable. I keep one upstairs as an ethernet bridge (no UPS and it has done fine).
Whether you're talking about routers or cable modems/DSL modems, the only way to ensure reliability is to fix the power supply. Are you running 12 gauge copper on a dedicated circuit to your router/switch/modem? Or just buy a UPS for $20-$30 and you can discontinue your daily or weekly reset of your cable modem. Your wireless access point will actually be on when you go to use it. And you can use your laptop or VoIP during a thunder storm.
No, I don't work for the battery company.
Same here. The condition that tripped the problem went as follows:
My laptop = Ubuntu (latest)
Wife's laptop = Vista Home Premium.
Both wireless.
We're surfing, everything is running great. I'd hit a site that had lots of images all on one page (think Fark's 'Photoshop this pic' page')
Bang, network goes dead.
I'd restart the router and my box would come back online no problem. Vista would not re-establish a connection. Repair (or whatever it's called in Vista) failed. We'd need to reboot her computer.
Searched the web and found that this same problem happens and seems to be related to the router.
Switched to a Netgear VPN824V3 and the problem has pretty much disappeared.
Four words: Switched Mode Power Supply. Switching supplies are extremely efficient and thus small. You've seen this already, there's one in your computer. That's how they can pack an 800+ watt supply in to something that small. You try and do that with a linear supply and it'll be massive.
Same deal for wall warts. Some companies still use linear supplies, but not many. It is to the point where SMPS is much cheaper to produce. They also have the advantage of being smaller, and running cooler.
You can see the technology at work in amplifiers. Have a look at Rotel's site sometime. Specifically, compare their old RB-1080 vs their new RB-1092. The RB-1080 is about twice the vertical size as the RB-1092 to house some large components (the transformer and the heat sinks mainly). However it outputs only 200 watts per channel where as the 1092 does 500. How? Well the 1080 is an older style amp. It uses a linear power supply, and class AB output. Thus it takes a lot of space and generates a lot of heat to do what it does. Not very efficient. The 1092 is a class D amp. It has a switching power supply and switching outputs. As such it is very efficient and produces little heat.
Now none of that is to say that Dlink isn't including poorly made SMPSes, however the fact that they are so small has nothing to do with their quality. You don't need big if you have efficient.