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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.
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 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."
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.
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)
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
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 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.
That's just stupid.
Honestly, who sacrifices convinience for security?
An SQL query goes to a bar, walks up to a table and asks, "Mind if I join 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.
I second this. I have a D-Link Gamer Lounge (DGL-4300). This is the most stable router I've ever owned. Thumbs up on the QoS, stability and speed (GbE). If I were able to run 'uptime' on it, I believe it would say close to two years (I live in Florida, but it's on a UPS). Oh, wait:
Connection Up Time : 617 day(s), 12:04:53
Sick.
My last router was a WRT54GL that decided to brick itself after about three months of DD-WRT. I think I should agree with some of the above posts that offloading network services can help these routers, but I'm not sure. I run my own DNS and DHCP, so this router has never had to bear that load.
http://www.southparkzone.com/episodes/1206/Over-Logging.html
I fear the Y2038 bug
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.