Good UPS for network equip?

Well, if I read your questoin correctly, you suspect interference as a problem, not power interruptions.

This means you must look for a UPS that converts AC to DC to AC all the time, and not one of the 'install next to your computer' ones that use AC in = AC out and only switch from DC to AC in case of an outage.

A filter may be more effective.

Thomas

router,

These are decent:

You are fooling yourself if you think a UPS will solve networking problems. If AC electric is a reason for network problems, then the solution begins by finding a defective safety ground or eliminating the power supply that retail lists for less than $50.

Solution to your network problem starts with running comprehensive diagnostic. One had intermittent problems. Ran the comprehensive diagnostic in the massive data exchange test

- usually the last and optional test. Eventually, a defective NIC would lock out under this massive data transfer. Such comprehensive diagnostics assume you have two NICs from the same manufacturer.

Plug-in UPSes, such as the recommended Tripplite, connect computer directly to AC mains when not in battery backup mode. Where is the protection? Furthermore, these UPSes typically output some of their dirtiest electricity when in battery backup mode. If a network was suffering from line noise, then power the computer from a UPS in battery backup mode. The network would crash immediately. If not, then AC mains noise is not a reason for network failure.

One example of a UPS under light load is demonstrated. When in battery backup, the 120 VAC output is two 200 volt square waves with a 270 volt spike between those square waves. Dirtiest electricity is from that UPS in battery backup mode. But not problematic to any properly constructed computer. If that noise caused computer problems, then the computer hardware was defective when purchased or assembled.

Find the problem rather than trying to cure a symptom. IOW first identify the reason for a problem before speculating - before 'fixing' everything.

Another 'suspect' is exist> Have one client that keeps having network lock up. Have replaced

On Tue, 20 Jul 2004 14:55:30 -0700, w_tom wrote (in article ):

When powering off the router and back on is the only way to bring the network back up again, this points to dirty power. I don't change cables, or reboot the computer, or dust off the router to bring up the network, I power cycle the router. It is the only way to fix the "lockup".

The router has been replaced once, hoping that it was defective. Symptom remained unchanged.

I'm open to other suggestions, but my diagnostics points to a power problem.

Thanks,

You don't indicate the manufacturer or model number of the router, but I'd also suggest that the occasional "lock up" that requires power cycling could be the result of a software bug in the product itself that might be overflowing the device's memory. Just a thought, but you might want to do a quick check on the specific make/model to see if there are known problems and if there is a newer operating system load or patch that addresses this symptom. Or, alternatively, replace with another (different) router and see if the problem goes away. (You indicated it was replaced once already, but possibly with the same make/model with the same inherent defect?)

Good luck.

Bob

network

reboot

cycle

problem.

How do you activate a computer's master reset after computer has locked? Either press the master reset button, or power down and up. Nowhere did this master reset solution indicate bad power. Demonstrated is that a suspected internal hardware problem can be cleared by the router's master reset circuit. A circuit that operates only when powered off then on.

Now what causes the internal computer and logic to lock up? And what specific diagnostic points to power problems?

Your symptoms only demonstrate that lockup can be temporarily eliminated by a master reset. What diagnostic program points specifically to power as reason for problem?

Did you run the comprehensive diagnostics as described in a previous post? If not, then experience from a few decades says you are still 'spinning wheels'. Provided in that previous post is how to obtain the missing and necessary facts.

For example, is problem in the router or is it something else? Based upon what was posted, we still don't even know that. Described were comprehensive tests executed from NIC to NIC both via a router and without the router. So far, I only read enough information to 'speculate' that the router might be a problem. And what kind of router? What is the networking type? 10Base2? Conventional 100 Mhz Ethernet? Whose router? For that matter, is it a router or a hub?

Currently posted is no single reason to suspect power as reason for failure. Currently posted are reasons to believe that a master reset inside router can clear the lockout. But that still does not say whether the master reset clears a problem internal to the router or a problem with a connected NIC. Run those manufacturer diagnostics and use alternative cabling to obtain useful facts. Currently provided is only enough information to speculate or to define necessary future tests.

For example, problem can be created if a long ethernet cable is not assembled using the correct matching pair of wires. And a master reset could clear that 'miswired cable' created lockout. Only one of many possibilities since we still don't have accurate facts such as results of diagnostic tests.

Environment: small 4-person medical office. These are not huge bandwidth-using people.

Equipment: 1 PC, 3 Macs connected via 10-baseT to Netgear RP614v2 router. Router firmware is current release.

Symptoms:

1. Every 2 weeks, or so, suddenly no one connected to the router can access the 'net. No one was attempting to use the internet at the time of the failure, they just found that their computer couldn't print to the network printer. I can ping the "immediate" router (that their computer is plugged into), but not the one beyond (that the printer and DSL router are plugged into).

Replaced the router, as it seemed defective.

Then, on one weekend, an office worker was present when the "lights flickered", and network symptom occurred. I started thinking about power problems, and office workers confirmed that the lights would flicker several times a week.

Restarting the router fixes the symptom, every time it occurs.

Understood.

I see no evidence that a cable has locked up the router. Have you experienced this?

Thanks,

You see no evidence that a cable has lockup up the router because you have not yet run those comprehensive diagnostics. You are not doing what your car mechanic must do to not be sued. You are not doing what your doctor does before perscribing medicine. You are speculating this must be a power problem only becasue the routers master reset cleared the problem. First thing you should have done is run those diagnostics. Make the intermittent into a solidly repeateable problem.

Again, do you know the cables are wired correctly internally? Did you run comprehensive diagnostics to see the problem, then swap out with a know good cable, run the diagnostic again, and see no failure? From the symptoms as described, a long list of reasons could create the problem. One of those reasons is most likely in a low bandwidth environment. One of many reasons for lockup would be a cable not properly assembled. Network would work sometimes; then eventually lock up. Lockup is then cleared by the router master reset that only occurs with power removal. And this is only one of many possible reasons for the failure.

With this one type of failure, you could ping all you want and that still would not create the failure. Again, I probably have a generation plus experience on you with this stuff. Experience based upon design - not just simplistic part swapping. Having been there, the quickest and most reliable solution to this problem was provide previously - including the loope. Having experience, the only reason a power glitch can cause your problem is if that entire line of routers is defective by design. Defect in all routers of that design which means that router works in 99 locations and becomes intermittent in one. Your symptoms are also of problems that have nothing to do with power. If you had a problem created by power, then the entire line of routers is defective - and you used a better design.

You did verify power by running an extension cord between outlets so that a meter can confirm wiring? If power was a problem, then the meter is the first thing you used to confirm building wiring (and no, those little cubes with three lights would not detect the type of failure you were looking for).

Diagnostics are so simple to obtain and execute that it takes longer to make a second trip to that office. Diagnostics were created to solve just this type of problem.

In the meantime, what did the lights on the router for each cable and on each NIC report both during operation and during the outage. Once problem happens, then which computers can ping or not ping which other computer (which is why you left a batch file script on the desktop of each machine so that the user can execute that test and report back).

Possible reasons for your failure: miswired cable. Impropely connected RG-45 plug to cable. Serious safety ground problem with the office wiring. Defective (intermittent) NIC in any one computer.

Restart> Environment: small 4-person medical office. These are not huge

Possibly a ferroresonant line conditioner might help in this situation.