Power Outage = Computer Harm?

[rfakhrai]

I'm looking to get some advice. I live in an area that is prone to common power outages. I have my machine hooked up to a surge protecting power strip but every time the power goes out and my machine shuts off abruptly I get a shiver up my spine. Am I hurting software/hardware components whenever this happens? I might consider buying a UPS if this is a bad thing.

[wizard10000]

Re: Power Outage = Computer Harm?

Surge protectors wear out, plus if you ask me a lot of them are useless. An decent but inexpensive UPS that'll send a heartbeat to the PC and the software to gracefully shut it down is the way to go. You can find inexpensive ones that'll provide a heartbeat to your PC over a USB or serial port and run it long enough for monitoring software on your PC to shut the machine down for around $50.

While you're busy surge protecting stuff it might be wise to note that a power spike over an Ethernet or modem port can kill your PC just as dead.

[rfakhrai]

Re: Power Outage = Computer Harm?

So I guess the answer is YES: THAT'S A BAD IDEA

Can you suggest any brands or give me an idea of what I should be looking for in a UPS you're describing. I have a 550W power supply but do I need to buy a UPS that's rated at >550W? That gets expensive quickly.

Also, what kind of software can help me with this? Thanks for your response.

[Qqmike]

Re: Power Outage = Computer Harm?

Some discussions on UPS:
http://forums.hardwareguys.com/ikonb...b87e1318bdda70
It's a very friendly board--you can also post your special questions.

[SteveRiley]

Re: Power Outage = Computer Harm?

Surge protectors wear out, plus if you ask me a lot of them are useless.

I used to work at a Radio Shack in high school and college (yeah, big surprise, haha). People would regularly come into the store and buy the cheapest "surge protector" they could for their multi-thousand dollar gear. I'd ask what they think they're getting protection from. "Like, surges, man, you know, during brownouts."

Simultaneous voltage spikes and sags? Uh, no.

What a lot of people don't realize is the cheap little metal-oxide varistors in those surge protectors are mostly worthless. Voltage spikes from lightning strikes far exceed the clamping voltages the cheapest MOVs can handle, and no MOV can protect against a voltage sag.

I'd explain that to obtain true protection requires investing in power supplies that isolate you from the city mains. "How much?" About $200 (late 1980s). No one ever bought power protection at that price.

[wizard10000]

Re: Power Outage = Computer Harm?

So I guess the answer is YES: THAT'S A BAD IDEA

Can you suggest any brands or give me an idea of what I should be looking for in a UPS you're describing. I have a 550W power supply but do I need to buy a UPS that's rated at >550W? That gets expensive quickly.

Also, what kind of software can help me with this? Thanks for your response.

There are a lot of ways to do this and not all UPS are supported, but I'd start here -

https://help.ubuntu.com/community/apcupsd

A 550w power supply doesn't mean your PC draws 550 watts - this UPS is about $85 but you'll save time configuring it because it should be pretty well supported -

http://www.newegg.com/Product/Produc...82E16842101339

If you'd rather not use an APC daemon see -

http://www.networkupstools.org/stable-hcl.html

[rfakhrai]

Re: Power Outage = Computer Harm?

Excellent! Thanks to both of you for setting me on the right track. I'll wait until the next pay check and do a little more research in the meantime.

[GreyGeek]

Re: Power Outage = Computer Harm?

I used to own and use an APC 500 Watt UPS. It had enough power to keep my desktop and monitor (I never plugged the printer into it) up for about 5 minutes when a power outage occurred. It had a test button which disconnected the power for a few seconds in order to test it.

One day, a couple of years after I got it, the power suddenly went out. So did my UPS. So did my computer. When this happened before I started using a UPS, I was running Windows (3.1WFWG and then Win95). It often meant a reinstall to recover, and I usually did an HD reformat to make sure the foundation was secure. (The NTFS is much better at recovering from a power cycle than FATS) The first time I had a power outage running Linux with my UPS I was stunned to see RH5.0 come back up, go through a chkdsk automatically, and repair some corruption. Everything worked! I disconnected the UPS and never have used one from then (1998) until I bought my first laptop in 2004. They have a built-in UPS!

My biggest concern was lightening strikes hitting the line somewhere close and causing a spike that would kill my equipment. Occasionally one would hear the first crack of lightening before realizing that a storm was approaching (I was really intent and focused while coding, and shut out the world around me, as my wife can testify). If my box wasn't hit on the first strike my first action was to grab the power cords going into the 6 socket adapter and yank them all out at once, to isolate my equipment. After the storm passed I plugged them back in and let the EXT2 (later EXT3 and now EXT4) file system do its thing. I have yanked the cables many times here in Tornado Ally, and I have never lost a single byte of data nor have I had to do a reinstall because of yanking the cables.

Now I just yank the power cord out of my laptop and work away till the storm passes, then plug it back in.

At work we had about 30 servers running NetWare and 3 or 4 running Linux. All were hooked to a BIG UPS with lead-acid batteries, designed to keep them running for about an hour or so, IIRC, until someone could drive into work and do an orderly shutdown if a problem occurred at night or over a weekend. I came to work one Monday and was told that the LAN would be down till noon. The power to the building had been interrupted by a Squirrel sacrificing his life (I later saw another do the same thing from my office window) in a search for nuts on a Sunday afternoon, and all of the servers went down instantly. The Linux boxes came right back up that afternoon with no losses. They had to recover NetWare and/or applications on most of the others, which took six MSCE's and their boss almost 24 hours, and required some data re-entry because the backups were still in process when the outage occurred.

[rfakhrai]

Re: Power Outage = Computer Harm?

Thanks for the anecdotes, GG. Your experience confirms what I've seen with the EXT4 FS so far. On at least a dozen occasions, I've lost power to this machine. And I've never seen any errors or problems arising with the OS.

What spawned my question behind this thread, however, is the hardware side of things. I've recently replaced my HDD and it got me thinking: how are these components affected by losing power abruptly. Surges are one thing; I do not live in an area where my house or the vicinity is struck by lightning. Most of the time the substation down the street has some sort of problem and we lose power for <5 minutes. But the effects of losing power abruptly on the hungry hardware components are still unknown to me. That's why I was considering a UPS. I need to do a little more soul-searching in the meantime

[GreyGeek]

Re: Power Outage = Computer Harm?

Personally, using Linux, I've found an UPS to be a waste of money and electricity, for the reasons I gave previously.

The hardest thing you can do to electrical equipment is to turn it off or on. It is during the electrical voltage and current spikes of those two events that most electronic parts (capacitors, transistors, diodes, EPROMS, etc..) fail. If the failure occurs during shutdown you won't find out about it till the next time you power up, so most people think the failures occur during power up, but that only when such failures become evident.

Even having an UPS won't filter those spikes or transitions that take place in the circuit boards during power down or power up. Those events are best controlled at the time of purchase, when one purchases the better designed hardware, which usually comes at a premium price. Take resistor ratings, for example. Say a design uses a resistor in a circuit that will require it to shed 1 watt of heat. A cheap PC will use a resistor that is rated to dissipate only 1.5 or 2 watts. An expensive design will use a resistor rated at 5 watts, or it will have cooling fins attached, to keep the resistor from over heating, which could permanently change its resistive value. The cheap machine's resistor gets hot repeatedly and its resistor value creeps out of design specifications, causing the circuitry to fail, intermittently or permanently, to do its design function. As a result, the video may black out, or the a pixel on the screen fails, or a a CDROM to make a lot of coasters, etc....

[wizard10000]

Re: Power Outage = Computer Harm?

IMO the correct answer is that as far as your data's concerned you don't want a single point of failure. Hardware can be replaced, data can't.

Although I do agree with GG about selecting quality components we disagree about the value of UPS, as although you may carefully select your motherboard a power spike can just as easily take out your hard drive - and recovering data from a failed hard drive costs hundreds or thousands of bucks.

So - when you look at data integrity you look at the whole picture with the idea of protecting the data, not protecting the hardware.

You back up religiously. The stuff that you *really* can't afford to lose you back up offsite. The data I can't afford to lose (tax returns, scanned copies of birth certificates, marriage license, military discharge papers, home mortgages, insurance policies, credit card numbers and so on) I encrypt with my own 2048 bit RSA key and store in the cloud. Most important is that I have the data in case my house burns down and that I control the encryption key. I store a copy of the key offsite in both optical and printed media. Since there really isn't a whole lot of data I absolutely can't afford to lose once I got this set up I only have to touch it once or twice a year to encrypt and upload a new tax return or something.

Stuff like email, pictures, snippets of code and documents that I could afford to lose but would be a pain in the backside if I did are automagically synchronized between my desktop and netbook once a day and the home directory on my desktop PC is rsync'd to an external drive nightly. I also have an external drive to back up my netbook, but since the netbook data is already synced up to the desktop PC it doesn't get used much.

Anyway, at the end of the day in order for me to lose my Really Critical Data both my house and the local bank where my safe deposit box lives would have to burn down. To lose the Kinda Important Data I'd either have to lose the house or at least three disk drives.

Hardware's cheap - it's the data that can't be recreated.

Okay, rant over.



edit: And one more thing since I'm on a roll this morning. An untested backup solution isn't a backup solution

[dibl]

Re: Power Outage = Computer Harm?

I'm pretty much 100% with the wizard on this one. Our two desktop computers each have a UPS, although I admit I haven't checked the batteries on either one for a year. We had a brief power outtage last week and the one computer that was on was OK for long enough for me to shut it down. The other one is on a UPS from the 1990s, and its switcher is too slow for current technology computer power supplies, so it does not actually prevent a power loss to the computer. But, as wizard says, that nice big battery and switching network provides a great target for spikes and surges, pre-computer, so I use it as a giant surge protector.

But the key to real data security is indeed the backup routine, and off-site storage, not protecting the hardware. The hardware will break, sooner or later, guaranteed.

[woodsmoke]

Re: Power Outage = Computer Harm?

Since several people have given very good answers I'll do two things:

a) second what they said
b) add a couple of oddments.

i) When one lives in a "development" or "rural" one is often "at the end of a line", or in the case of the development, the group of houses is "at the end of the line".

A lightening strike that occurs a long way away can "run down the lines"(path of least resistence, until it hits the house or group of houses at the end.

A "ground wire" is fundamentally useless in terms of trying to take care of the situation.

I have several actual experiences with this,

A) an incenerator was moved into the area and it was continually being "knocked out" by lightening even though all of the smart people had done all of the stuff to "get it up to specifications"... a "country bumpkin: said that for a fee, up front of course, he would solve their problem, and the answer was a WELL CASING drilled throug into bedrock and all of the "groud wires" converted to like 5 gauge and ran to it. worked like a charm.

The moral to the story is that a lot of stuff that is sold is done so for "peace of mind" not to actually work.

B) we had no problem with lightening strikes until a pwer pole that was BEYOND us was removed by the power company, th eelectricity which normally ran to it now ran to our house.

C) I worked for a welderthat had THREE....."manual".... circuit b reakers between the line and the welders. When a big storm was coming he opened all three, but even with that, one really massive storm jumped all three into a welder and it had to be replaced.

Physical seperation( in terms of "cable/ethernet/etc, is about the only way to remove any chance of a problem and then have the UPS have several circuit breakers in front of it.

One last thing is to reiterate what GG said. I keep all of my data offboard on both ann exgternal HD and on DVD. I leave the computer running all the time with the side of the machine removed and multiple fans cooling it.

If there is a big sgtorm, I turn it off, remove all plugs and cables and read a good book.

woodsmoke

[rfakhrai]

Re: Power Outage = Computer Harm?

I'm not too sure how this turned into a thread about proper backup solutions. I think we all have our own little quirky ways of backing up data and the most important information I have on this computer is my thesis. But that -- as well as everything else -- is backed up in 2 different sources.

ANYWAY! I was merely being shallow. I don't want my beloved machine to suffer the injustices of a voltage dip. Rest assured, my data is safe and my hardware may or may not be.

Thanks for the participation, guys.

[GreyGeek]

Re: Power Outage = Computer Harm?

Did someone say "thesis"?
8)
What is it about?