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Comments

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GoPro Project Claims Technology Is Making People Lose Empathy For Homeless

advid.net Re:Romani =! homeless of the streets (311 comments)

Even if you're honest, almost everybody will treat you like a criminal. Sooner or later, there is no choice but to prove them right or starve.

Actually you also confirm that they are criminals ? I find it quite ironic, but I understand what you mean: not inherently criminals but turned into because of the rest of the world.

However your rationale does not explain what I have experienced from them.

Also, their kids have pretty much a hard time in school due to bullying, they really need to hang on, but they can achieve a decent scholarship if they really want to and get out of their slum. And become a lawyer! I know one, she succeeded (and no longer looks like one of them).

And again: this is off topic, I won't go further in this discussion.

yesterday
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GoPro Project Claims Technology Is Making People Lose Empathy For Homeless

advid.net Romani =! homeless of the streets (311 comments)

I will not comment on your rant about Romani, everyone in Europe may have his own experience regarding those people, and I do as well.

However, mentioning this group seems a bit off-topic, since there are not homeless living in the street:
They always quickly setup their slum camp in any 'free' area they can find.
Those are not great homes, but a two years old slum camp will have upgraded the garbage tents into small homes with heating, electricity and TV Sat.

yesterday
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Intel and SGI Test Full-Immersion Cooling For Servers

advid.net Re:How about Silicone oil ? (101 comments)

Their fluid is boiling, phase transition takes a lot of heat out without pumping anything.
If not, you need to pump fluid between boards, this require more space and energy, even more with a thicker fluid.

about a week ago
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How Riot's Social Scientists Fight League of Legends Trolling

advid.net Re:These are griefers, not trolls. Trolling is fun (116 comments)

If somebody is truly upset, however, I would not, could not, continue to deride them. So that's where the fine line may be drawn.

Oh dear... then you missed the utter ecstatic joy of viciously trolling a moderator until he quit his job, while pissing off the whole community who praise him as one of the best ever.

Err... wait... did I misssed the anonymous toggle ?

about a week ago
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Australia May 'Pause' Trades To Tackle High-Frequency Trading

advid.net Re:HFT = a cost to society (342 comments)

You are not the devils advocate.

Your argument boils down to :
" Any pointless activity that consume goods is good for the economy. "

If you think this kind of behaviour drives us in the right direction for the material well-being, you must be quite an economist ! :)

about two weeks ago
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Australia May 'Pause' Trades To Tackle High-Frequency Trading

advid.net HFT = a cost to society (342 comments)

What really annoy me with HFT, besides not being "fair", it that it as a cost and that the society doesn't benefit from it.

Building a stock exchange with top-notch computers if fine, since there is a need fulfilled here for our society.

But building new warehouses as close as possible to stock exchange computers to house top speed fiber connected computers, just to lower the delays from 600ms down to 10ms or so, to allow HFT, is a waste of resources.
No one needs that, it's just a smart way to build a sucking vampire over information systems. And this cost is always somehow reflected to society.

One big bank of my country paid a lot to move all its crucial infrastructure abroad, in such new buildings, to be able to compete in HFT.
Who's paying for those efforts? The company, the bank, instead of doing something more useful to society (investments to improve their services, etc).

about two weeks ago
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Algorithm Challenge: Burning Man Vehicle Exodus

advid.net Re:Proxy encampment and pre-lane spools (273 comments)

The main question I had upon reading this, is whether there is space for the buffer parks.

You may have a look to aerial views of the event: there is plenty of space in the desert. However I don't know if they are limited by law or regulations.

This idea is indeed a mitigation, you perfectly understood my point.

about two weeks ago
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Linus Torvalds Suspends Key Linux Developer

advid.net Short story: See to what Linus responds (641 comments)

The message to which Linus responds is also interesting:

Short story:

The systemd guy uses the debug keyword on kernel command line to spool a huge log - which can hang the boot process, and that is the problem.
Then the same guy claims that the debug keyword is generic so it can't be reserved by the kernel, even if it's been used first by it since a long time...

I can say that Linus is right there, for sure. He's maybe too kind...

about two weeks ago
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Algorithm Challenge: Burning Man Vehicle Exodus

advid.net Proxy encampment and pre-lane spools (273 comments)

I think I have a better idea, since the problem is to wait in the queue for hours:

- Just one lane, with a known 1000 vehicles/hour limit.

- Have 3 or 4 "small" buffer parks (500 vehicles each) to wait with better conditions than in the main waiting line.

- Note: each vehicle in a proxy encampment has left its own main camp, so everything is packed, done, the driver has the key, etc.

- Every 30 mn, give the go for the next batch, so they start queueing, if someone stays the park (lost key or driver somewhere else), he will be soon surrounded by the new vehicle pool and will have to wait for the next round.

This way we have :

- one short main waiting line on exit

- 3 or 4 small dedicated parks next to main exit (worth 2 hours of line feed), people ready, waiting in better conditions than in lane. They know precisely when they will be going in the main line.

- the main camp, people getting ready, waiting for a proxy park to be freed.

If some people are willing to queue for more than the total pool time, let them fill a new proxy park and wait there.

about two weeks ago
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Gunshot Victims To Be Part of "Suspended Animation" Trials

advid.net April Fool's day : new date in march ? (357 comments)

Is it April Fool's day right now on /. ?

Leader's haircut, suspended life, ... what's next ?

about three weeks ago
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3D Printing: Have You Taken the Plunge Yet? Planning To?

advid.net Pro/Desktop and Internet 3D printing: Success ! (251 comments)

I've successfuly designed a few parts (parametric) with Pro/Desktop Express (outdated software but the best I've used so far).

I've successfuly printed those parts at Shapeways.

The nylon powder is fused by laser. Parts are thin and quite stiff. Good point. This kind of making is really not affordable for hobbyists.
The metal printing is okay, strong but I noticed a slight deformation. Good enough for jewelry.

I'm not looking in buying any 3D printer. Parts won't have the same quality as the one printed by SLS and I don't need to print that much cheap parts.

about three weeks ago
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New Facial Recognition Software May Detect Looming Road Rage

advid.net Mood based dynamic car color (133 comments)

I suggest that the car's outside color changes according to the driver's mood.

Sleepy driver = night blue
Nervous driver = pulsing bright red
Relax driver = apple green with dark green waves
Raging driver = blood red with yellow dots
...

about a month ago
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Paris Bans Half of All Cars On the Road

advid.net Timely Car Pooling (405 comments)

Testimony from a french driver with even plate (the restricted ones): he used the car pooling rule to be able to drive, but he droped the last passenger less than 1km from his own destination and was fined just after that... 22€ thank you.

about a month ago
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Alibaba Confirms Plans To Offer IPO In US

advid.net Re:My story with Alibaba (93 comments)

I'm also curious : "how did you go about selling the pens" ?
Can you answer to guises (2423402) please ?

about 1 month ago
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How Do You Backup 20TB of Data?

advid.net Re:Please post Tape backup ref (983 comments)

Here is what I've found, here (my emphasisi):

First step in LTO-6 (native 3.2TB, 210MB/s) was made in June 2011 when the three technology providers announced the availability of licenses for this format. But later these specs were reduced to only native 2.5TB (+67% compared to LTO-5) and 160MB/s (a mere +15%). Generally, the capacity of the LTO tape follows current highest capacity of HDD. But it's now 4TB uncompressed and LTO-7 is supposed to be native 6.4TB (and 315MB/s) and will be there probably in at least two years.

So it looks like LTO-6 would backup 4TB uncompressed, pushing the original standard a little bit (no pun intended).

about a month ago
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How Do You Backup 20TB of Data?

advid.net Re:Please post Tape backup ref (983 comments)

Thanks.

Hum... the LTO-6 tapes are only 2.5TB native ( 6.5TB with 2.5 compression, that won't apply to media files).
Someone said there's 4TB tapes now, it looks so but news about this are rare...

about a month ago
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How Do You Backup 20TB of Data?

advid.net Please post Tape backup ref (983 comments)

To /.ers saying that 1TB+ tapes would be a good idea to do this backup, please:

Add some references and price of such hardware and media that would suit best home usage.

about a month ago
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Japan Marks 3rd Anniversary of Tsunami Disaster

advid.net Onagawa linked article : Worth reading ! (77 comments)

Onagawa plant article is very insteresting.

It explain how a more stressed nuclear plant on the sea shore hadn't catastrophic consequences after the tsunami:
Safety culture impulsed by a man.

Onagawa was only 123 kilometers away from the epicenter—60 kilometers closer than Fukushima Daiichi—and the difference in seismic intensity at the two plants was negligible. Furthermore, the tsunami was bigger at Onagawa, reaching a height of 14.3 meters, compared with 13.1 meters at Fukushima Daiichi. The difference in outcomes at the two plants reveals the root cause of Fukushima Daiichi’s failures: the utility’s corporate “safety culture.”
[...]
Yanosuke Hirai, vice president of Tohoku Electric from 1960 to 1975—a time period that preceded the 1980 groundbreaking at Onagawa—was adamant about safety protocols and became a member of the Coastal Institution Research Association in 1963 because of his concern about the importance of protecting against natural disasters. With a senior employee in upper management advocating forcefully for safety, a strong safety culture formed within the company.

See what they did in Onagawa in the article: plant built on higher ground, five times the estimated average tsunami height, plus tsunami response aware teams.
Tepco did the oposite: "to make it easier to transport equipment and to save construction costs, in 1967 [they] removed 25 meters from the 35-meter natural seawall of the Daiichi plant site" !!!

about a month ago
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Ask Slashdot: Does Your Employer Perform HTTPS MITM Attacks On Employees?

advid.net HTTPS Proxy Interception : detection (572 comments)

Shall we focus on how one can detect this situation ?

Case 1 : One have access to the network
- Bring you own trusted device: laptop / tablet / ... Start your own browser, see the certificate warning.
Could the device be also abused ?

Case 2 : One has a limited access to the system
- Start your own Portable Firefox on USB key, with standard certificates. See the certificate warning.
Is there any other tool ?

Case 3 : One has access to a kiosk or similar looked system
- Assume everything is logged, don't trust. Poor configurations may be worked around to visit any web site, but don't type any password on it.

about a month and a half ago

Submissions

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Wold First In-Man Total Artificial Heart Implantation

advid.net advid.net writes  |  about 4 months ago

advid.net (595837) writes "The designer and developer of the world's most advanced total artificial heart project announces the first implantation of its artificial heart, as part of its feasibility study and in accordance with the approvals granted by the French health authority and the ethics committee.

This artificial heart is total, biocompatible and self-regulated, it slows down or accelerates when needed. The external battery is on a belt.

The procedure was performed on December 18, 2013 by the Georges Pompidou European Hospital team in Paris — a world first.

This first implant went smoothly, with the prosthesis automatically providing normal blood flow at a physiological rate. The patient is currently being monitored in intensive care. He is awake and able to talk to his family.
English article
Two videos about this total artificial heart"
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Lightsaber hold-up in minimarket

advid.net advid.net writes  |  about a year ago

advid.net writes "Two thieves robbed a convenience store with a lightsaber to threaten two employees.

They ask them to put the cash in a bag. The staff complied, and the robbers got away with about 250 €.

The incident did not cause any casualties but the employees were very shocked."

Link to Original Source
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What hapenned to slashdot interface ? Why ?

advid.net advid.net writes  |  about a year ago

advid.net writes "Today I see that Slashdot has a new web interface, no more on a single extensible page whith "more stories" button. Now there are previous and next buttons to switch from one age to another...

Why did they changed this ? Why do they do like the others web sites ?

Is there any way to get back to the single dynamic page ?"
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Malaysia deports Saudi blogger over tweets

advid.net advid.net writes  |  more than 2 years ago

advid.net writes "As one blogger is freed, another is sent back home to face death penalty:

Malaysia has deported a young Saudi journalist who is wanted in his home country over Twitter posts about the Prophet Mohammad that sparked calls for his execution, the Malaysian government has confirmed.

Hamza Kashgari, who was detained in Malaysia on Thursday after fleeing Saudi Arabia, left the country in the custody of Saudi officials on Sunday, a statement of the Malaysian Home Ministery said.

Kashgari, a 23-year-old Jeddah-based newspaper columnist, fled to Muslim-majority Malaysia after making comments on the microblogging site deemed insulting to the Prophet Mohammed, which fuelled a surge of outrage in the kingdom.

Kashgari apologised for his comments and said he was being made a he a "scapegoat for a larger conflict". Insulting the prophet is considered blasphemous in Islam and is a crime punishable by death in Saudi Arabia.

"

Link to Original Source
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Megaupload User Data could be gone soon

advid.net advid.net writes  |  more than 2 years ago

advid.net writes "According to AP, Megaupload User Data Could Be Gone Thursday.

Megaupload hires outside companies to store the data. Those companies haven't been paid since the Mega-raid: Mega-money is frozen.

Thus 50 million Megaupload users have data in danger of being erased, like for any paid account that is no longer paid by customer."
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Macroscopic wave–particle duality

advid.net advid.net writes  |  more than 2 years ago

advid.net (595837) writes "A 'walking' drop on a liquid surface behave like a particle with wave properties: diffraction, interference patterns, vibration quantization.

First, in a vibrating container they put a liquid like silicon oil, vibrations are just bellow the Faraday instability threshold. Then a drop of the same liquid is dropped on the surface, but it does not coalesce, it bounces. And further bounces make a static wave pattern on the liquid surface just bellow the drop and its immediate neighborhood. As the spike grows, instability increases and the drop slides down the spike, and start moving horizontally.

Then they have a combo object drop+wave pattern moving at 1/10th the speed of wave in this liquid, straight. They call it a walker.

What is really amazing is that the wave pattern below the drop has some kind of memory: it has accumulated energy from several drop bounces. It can also make the drop see "forward", as the small wave pattern bounces back from nearby obstacles. So the drop is "aware" of its environment and "recall" the path it has followed.

Diffraction is observed and explained by the multiple reflexions the wave makes when the drop passes through a small hole, randomizing the wave pattern and the angle of the path afterward. Interference patterns observed are explained a la de Broglie: as the drop passes through one of the two holes, its associated wave passes through both, carrying forward the message of the second hole to the drop and changing the statistical repartition of the drop's path direction. One more stunning result: they are circling the drop by moving the container (Coriolis), then the associated wave adopts a discrete series of pattern, depending on the speed and radius. Very much like the energy quantization of electrons.
English (and French) abstract
A short article (French but it has photos and formulas)
Full thesis (French,10Mb)"

Link to Original Source
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Ask Slashdot: Duke Nukem Unleashed, what gameplay?

advid.net advid.net writes  |  more than 2 years ago

advid.net (595837) writes "The long awaited Duke Nukem Forever, the king of the vaporware, was — at last — finished this year. During those years I noticed that the Duke has many followers here on /.

This is why I ask the crowd:
What would you have liked to get instead of this disappointing game?
Or what the next Duke Nukem should be like ?

It seems everyone agrees with games reviews: they took out the fun that DN3D once had.

Obviously we want back:
maps free to explore, no more lame disneyland path to follow like a track.
10 weapons to carry (not counting fists and boots), quick change by keyboard (PC gamers), because choosing the perfect weapon for a job is fun.
fast Duke, not one that can't breath after a 10s sprint. And higher jumps also.

These are the minimum requirements.
And the paradox is that going back to this old gameplay would lead to a new kind of FPS among those we have today. Don't you think so?

Along with that I wonder if you have some other ideas.

Maybe the Ego thing is a good idea to keep, or some combination with life points ?

Interaction with the maps is poor in Duke Nukem Forever, it could be improved with the next Duke Nukem, but I know it is quite some work for developer teams. I think it doesn't matter if you can't destroy walls, doors, and furniture; but some new unusual and innovative map and object interactions should be worked out for the fun and the gameplay.

Then, humor and story are more a matter of taste.
I would suggest a worldwide contest to send new jokes, they will be kept secret unless discarded by some kind of small team of dedicated fans.
Collaborate to build a new story without telling the whole picture or all the details to gamers: do you have any experience in such participation?

Also: dying. Duke should die with more class. Bloody broken glasses aren't enough. Different kinds of death, maybe from another point of view, not with Duke's eyes.
By the way, are the other camera angles gone?

One last question:
How could we call the next Duke Nukem adventure ?
I suggest Duke Nukem Unleashed.
(by contrast to Duke Nukem Forever, very restrained)

I hope someone will be able to push those requirements and your answers to an editor, so the Duke that we like can come back... when finished !"
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MozilllaNews taken over by CyberSquatter

advid.net advid.net writes  |  more than 2 years ago

advid.net (595837) writes "As I browsed through MozilllaNews links on my Slashdot page, I realize that they all direct to the same cybersquatter page with a very poor content.

What happened? Did they forgot to renew the domain subscription?

Should Slashdot remove this section until they get back their domain?"

Link to Original Source
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The old Prophecy trick strikes in StarCraft II

advid.net advid.net writes  |  more than 3 years ago

advid.net writes "When a writer just doesn’t know how to tell his new story or, worse, when he hasn’t yet any story to tell but needs to write one, he can make up a prophecy. To resort to a prophecy is an easy trick to make a story. He doesn’t even need to justify anything, to explain where the prophecy comes from or why it says so. The characters keep telling “the prophecy says...” or “according to the prophecy...” without any background or justification. The prophecy is just there. And of course each time a character talks about the prophecy, he is at least respectful and usually speaks with solemnity and deep eyes. Even the bad guys believe, and if someone laugh at it, then this is the moron, the dumb guy. Nobody in the story will challenge the prophecy or say it is crap or bullshit.

The writer can also lengthen the story by telling us how the characters discover the prophecy. Well, first they will have heard about it. Then they have to find the writings or someone telling the prophecy to them. Before that, they will have to get somewhere, break in something, quite a journey. Then, once the prophecy obtained, they need to decode it and interpret it. Besides later another reading of the same text will lead to another conclusion, this is a cheap way to start over a new stunning adventure in the story.

Everyone knows films, books, games which have used this prophecy trick as an easy make-up for a shallow story.

Why am I telling this ? Because I’m just tired of those prophecy stories, I’m sick of it. Enough. Please, can someone in Hollywood, in editors companies, in video game teams, tell them to stop using this trick ?

Last time I’ve seen this trick used, it’s in StarCraft II campaign (crystal missions). I though “Oh! No! Not again! Aaaargh ! The old Prophecy Trick strikes again! Damned! Shame on SC2 team.”

Don’t get it wrong: this game is really great. But come on: do we really need to be treated like that? (And the Zerg burrow capacity explanation remind me the midi-chlorians in Star Wars 1... What a pity to add non-sense to the mystery.)

Does this prophecy trick also upset you and did you saw it in use recently ?"
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Car black box camera DVR : efficiency and law ?

advid.net advid.net writes  |  more than 3 years ago

advid.net writes "Just in case I get involved in an car accident, I want to install one of those car black box to record a front view video while driving.

I believe it could help prove which side was wrong. It could be usefull if I'm wrongly accused of speeding or having a red light. Or to know who has damaged the car while parked.
Some of those devices can record two video chanels, 3D g acceleration, GPS position (with speed), HD video (for plate and face identification).

I'm sure some of you have experimented such geeky device :)

Could you share your experience ? Is it efficent ? Is there any problem with it regarding your country/state's law ?"

Link to Original Source
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March 25th : first Procrastination Day

advid.net advid.net writes  |  about 4 years ago

advid.net writes "Today, March the 25th of 2010, is the first worldwide procrastination Day.

As you may have guessed, the purpose of this day is to celebrate the procrastination by deferring every today tasks to tomorow.

I just wonder... could we celebrate this day a bit later ?"

Link to Original Source
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France threatens music majors for catalog release

advid.net advid.net writes  |  more than 4 years ago

advid.net writes "French President N. Sarkozy asks for the majors to release their catalog to all platforms of music downloading.
The majors have fought against this proposal suggested by a government commission. They didn't expect such requirement during the president's 2010 wishes. Universal COE was standing KO as he thought that his lobbying has been successful.

Translation of the last part:
N. Sarkozy gives a year to the majors so they can negotiate rights and "liberate" their music files on all platforms. Failure to do so, they will have to "bargain rights under the law of compulsory collective management through civil societies," he said. For the majors, it's everything they hate! Because a civil society distribute revenues without necessarily benefit producers at the expense of the authors ...
The President went even further by launching the idea of a unique gateway reference all the catalogs and music videos. "Do not complain that others do better than us, if we do not give us the means to do as well as they do," he said. If Sarkozy does not falter, it announced that the time of the omnipotence of American portals on cultural content may be gone soon ..."

Link to Original Source
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Cowboy Neal 3D soon available

advid.net advid.net writes  |  more than 5 years ago

advid.net writes "According to this thread there are plans to produce some Cowboy Neal 3D replicas through a rapid prototyping process.

I wonder if some other Slashdot celebrities would be available too.

<<Can we print...
7- Cowboy neal 3D?
Still waiting for the model...

Furthermore:
...
— the 4th option silently replace uploaded models by the Cowboy Neal 3D model (coming soon).>>

I can't wait to see how it looks like!"
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Pool: You're most unlikely to believe in...

advid.net advid.net writes  |  more than 6 years ago

advid.net writes "You're most unlikely to believe in...

  • Aliens came/are on Earth
  • The water powered engine
  • Telepathy
  • Windows without bug
  • God
  • Linux on desktop market
  • Year -6001
  • CowboyNeal pool option success
"
top

advid.net advid.net writes  |  more than 7 years ago

advid.net writes "According to this European think-tank, several practical consequences of the unfolding crisis will converge in April 2007, some of them are:
  • Acceleration of the pace and size of bankruptcies among US financial organisations: from one per week today to one per day in April
  • Spectacular rise of US home foreclosures: 10 million Americans out on the street
  • Accelerating collapse of housing prices in the US: — 25%
  • Entry into recession of the US economy in April 2007
  • Precipitous rate cut by the US Federal Reserve
  • Sudden drop of US dollar value against Euro, Yuan and Yen

About home foreclosures they mention Beacon Journal 11/01/2007, United Business Media 12/02/2007, Austin Business Journal 26/01/2007 and CNN Money on 25/01/2007.
They also mention scores of blogs appearing on the web and trying to review the on-going housing disaster and the stream of human tragedies, for instance My Real Estate Money or Foreclosure Pulse"
top

advid.net advid.net writes  |  more than 7 years ago

advid.net writes "This survey about slashdot made me wrote some suggestions...

  • A kind of Slashdotpedia: after an interesting question I gather the best slashdoter advices and my own search to make a journal entry. I suggest that I could back-link my journal from the article, even if archived. Then anybody browsing the article later could see that a guy has made a summary, a best of, enriched with his own work. Also those slashback summaries could be listed in a slashdotpedia section for great value added content (from a nerd point of view). See my three journal entries as an example.
    This mod is an easy one, few resource needed, work done by dedicated /.ers

  • As a registered user I'd like to know which issues I've seen (loaded/clicked) and which articles also. Slashdot would need to keep a database of this, I guess you can't afford such a load. Benefit: I can read later just what I've missed, I don't need to keep track of read/unread items.

  • I like those topic pics :) showing up along with articles, but we should see more often two pictures for an entry that could fit in several sections. I guess those new tags can help also.

  • There's some space on the title bar that could be used for this:
    Display a kind of flag array (very small icons) to tell what is the mood of the discussion. Then we could at a glance see that they started (mainly) to joke / troll, or that they are serious with great feedback. It's a kind of automatic tagging but not for topics/content, only for mood/kind-of-answers/readers-behaviour.
"

Journals

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Friends and Foes

advid.net advid.net writes  |  more than 6 years ago As I've reach the 200 friends limit on slashdot, I decided to keep track of certain friends (confirmed) or to queue new ones in case a friend is disapointing me and frees a slot. This is sad, I hope the 200 limit will be raised...

Confirmed are protected against unfair deletetion in case I really want to bring a new friend in and need to neutralize a random friend. Challenged may be deleted from friend list later.

Confirmed friends
http://slashdot.org/~LWATCDR
http://slashdot.org/~Ironsides
http://slashdot.org/~LionKimbro
http://slashdot.org/~NMerriam
http://slashdot.org/~misanthrope101
http://slashdot.org/~jgoemat
http://slashdot.org/~Grendel+Drago
http://slashdot.org/~Mark_MF-WN

Challenged friends
http://slashdot.org/~Opportunist
http://slashdot.org/~Teancum
http://slashdot.org/~geekoid

Queued friends
http://slashdot.org/~Demon-Xanth
http://slashdot.org/~dpilot
http://slashdot.org/~Sax+Maniac
http://slashdot.org/~Alzheimers
http://slashdot.org/~MaWeiTao
http://slashdot.org/~FireFury03
http://slashdot.org/~bentcd
http://slashdot.org/~fotbr
http://slashdot.org/~skrolle2
http://slashdot.org/~Chris_Mir
http://daleglass.net/
http://slashdot.org/~Maondas
http://slashdot.org/~babbling
http://slashdot.org/~evanbd
http://slashdot.org/~skam240
http://slashdot.org/~innerweb
http://slashdot.org/~tamnir
http://slashdot.org/~Heir+Of+The+Mess -
http://slashdot.org/~jstomel
http://slashdot.org/~etherlad
http://slashdot.org/~MightyYar
http://slashdot.org/~BakaHoushi
http://slashdot.org/~scotch
http://slashdot.org/~erroneus
http://slashdot.org/~tgibbs
http://slashdot.org/~Smidge204
http://slashdot.org/~sqrt(2)
http://slashdot.org/~mha
http://slashdot.org/~Creosote
http://slashdot.org/~Aglassis
http://slashdot.org/~exploder
http://slashdot.org/~SanityInAnarchy
http://slashdot.org/~Hatta
http://slashdot.org/~RobDude
http://slashdot.org/~ChronosWS
http://slashdot.org/~Belial6
http://slashdot.org/~jawtheshark
http://slashdot.org/~eclectic4 ++ (dec2013: last jan2010)
http://slashdot.org/~eldavojohn
http://slashdot.org/~flyingsquid
http://slashdot.org/~MightyMartian (but foe of friend)
http://slashdot.org/~thynk
http://slashdot.org/~Dhrakar
http://slashdot.org/~plnrtrvlr
http://slashdot.org/~unapersson
http://slashdot.org/~Khazunga
http://slashdot.org/~djmurdoch
http://slashdot.org/~Fuzzums
http://slashdot.org/~xstonedogx/
http://slashdot.org/~Magic5Ball/
http://slashdot.org/~Just+Some+Guy
http://slashdot.org/~giminy
http://slashdot.org/~steelfood
http://slashdot.org/~Kent+Recal
http://slashdot.org/~RAMMS+EIN/
http://slashdot.org/~thsths/
http://slashdot.org/~spun
http://slashdot.org/~sm62704 +++ (dec2013: last sept2008)
http://slashdot.org/~Andy+Smith rel +++ (dec2013: last jul2012)
http://slashdot.org/~Ethanol-fueledrel++ (dec2013: last mar2012)

Foe
http://slashdot.org/~mapkinase

investigate
http://slashdot.org/~twitter/

check to eject Minwee (522556)

EDIT Dec2013: it looks like the 200 friends limit have been raised, so I digg some queued friends to friend theml...

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Backup software & organization (slashback)

advid.net advid.net writes  |  more than 7 years ago Backing up a Linux (or Other *nix) System

Here are some valuable thoughts, I'll re-write something more synthetic later...

From digitalhermit (113459):

I deal with some aggregate 2 terabytes of storage on my home file servers. What works for me won't work for an enterprise corporate data center, but maybe some things are useful...

I think the article does a good job of explaining how to backup, but maybe just as important is "why?". There are some posts that say put everything on a RAID or use mirror or dd. What they fail to address is one important reason to backup: human error. You may wipe a file and then a week later need to recover it. If all you're doing is mirroring or RAID, no matter how reliable, your backups are worthless.

There's also different classes of data. I have gigabytes of videos. Some are transcoded DVDs, some are raw footage. If I lose all my transcoded DVDs it's not as critical as if I lost raw footage. Why? The DVDs can be re-ripped. It will take a long time but the data can be recreated. For the raw footage it's different, even if I keep the original Mini-DV tapes, because re-recording the video from tape won't guarantee that the file is identical. If the file is different then the edits will be different. Then there's also mail spools, CVS, personal files, etc..

What I've found is that I archive my DVD rips once every few months. Other stuff is backed up once a week to another file server.

I could care less about the OS. THe file server runs FedoraCore5. The only thing I keep is the Kickstart file so that I can rebuild it within a matter of minutes then restore the data from archives. This is just a matter of copying a samba configuration and restarting.

For the web server, all content is kept within CVS. If the web server fails, it's just a matter of rebuilding the image and pulling the latest copy from CVS. Fifteen minutes to re-image the OS. Five minutes to pull down the latest content.

For DNS, initial configuration for 8 domains is done by a perl script that auto-creates the named.conf and all zone files. Then I just append the host list to the primary domain. Ten minutes at most.

Home directories are centralized on a file server using OpenLDAP and automounts. One filesystem to backup makes it easy.. By being easy it means it gets done automatically.

Other "machines" are virtual and these are copied to DVD whenever something drastic changes (e.g., major upgrade).

From swordgeek (112599):

When you work in a large environment, you start to develop a different idea about backups. Strangely enough, most of these ideas work remarkably well on a small scale as well.

tar, gtar, dd, cp, etc. are not backup programs. These are file or filesystem copy programs. Backups are a different kettle of fish entirely.

Amanda is a pretty good option. There are many others. The tool really isn't that important other than that (a) it maintains a catalog, and (b) it provides comprehensive enough scheduling for your needs.

The schedule is key. Deciding what needs to get backed up, when it needs to get backed up, how big of a failure window you can tolerate, and such is the real trick. It can be insanely difficult when you have a hundred machines with different needs, but fundamentally, a few rules apply to backups:

For backups:
1) Back up the OS routinely.
2) Back up the data obsessively.
3) Document your systems carefully.
4) TEST your backups!!!

For restores:
1) Don't restore machines--rebuild.
2) Restore necessary config files.
3) Restore data.
4) TEST your restoration.

All machines should have their basic network and system config documented. If a machine is a web server, that fact should be added to the documentation but the actual web configuration should be restored from OS backups. Build the machine, create the basic configuration, restore the specific configuration, recover the data, verify everything. It's not backups, it's not a tool, it's not just spinning tape; it's the process and the documentation and the testing.

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Slashdot survey: more suggestions

advid.net advid.net writes  |  more than 7 years ago This survey about slashdot made me wrote some suggestions...

  • A kind of Slashdotpedia: after an interesting question I gather the best slashdoter advices and my own search to make a journal entry. I suggest that I could back-link my journal from the article, even if archived. Then anybody browsing the article later could see that a guy has made a summary, a best of, enriched with his own work. Also those slashback summaries could be listed in a slashdotpedia section for great value added content (from a nerd point of view). See my three journal entries as an example.
    This mod is an easy one, few resource needed, work done by dedicated /.ers
  • As a registered user I'd like to know which issues I've seen (loaded/clicked) and which articles also. Slashdot would need to keep a database of this, I guess you can't afford such a load. Benefit: I can read later just what I've missed, I don't need to keep track of read/unread items.
  • I like those topic pics :) showing up along with articles, but we should see more often two pictures for an entry that could fit in several sections. I guess those new tags can help also.
  • There's some space on the title bar that could be used for this:
    Display a kind of flag array (very small icons) to tell what is the mood of the discussion. Then we could at a glance see that they started (mainly) to joke / troll, or that they are serious with great feedback. It's a kind of automatic tagging but not for topics/content, only for mood/kind-of-answers/readers-behaviour.

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Ideas for a Home Grown Network Attached Storage (slashback)

advid.net advid.net writes  |  about 9 years ago Summary for this thread :
Ideas for a Home Grown Network Attached Storage?

[...]I would like to build my own NAS and am interested in hardware/software ideas. While the small form factor PC cases are attractive, my NAS will dwell in the basement so I am thinking of a cheap/roomy ATX case with lots of power.[...]

Notice: this text is a mix of several authors plus personnal updates, I thank everyone. This time I tried to credit authors from /. crowd ;-)

My conclusions are at the end along with request for comments.

from the /. crowd :

General advice

One big growable partition: Take a bunch of disks, turn them into RAID5 array. Make a logical volume (LVM on Linux) and add the RAID-array to it. Create a growable device on the LVM and format with a standard growable FS.
When you get new disks simply create a new RAID5 array and add that to the logical volume and add to your current and grow the FS on it.

You don't want everything on one big RAID0, I lost 200G of data that way. I can say I'll never do that mistake again.

FileSystem type

Common linux file systems (ext, reiser, etc) contains critical data-losing type bugs on file systems bigger than 2TB, except XFS. This was found to be the case in even the most recent 2.6 kernels.
Tony Battersby posted a patch to the LBD mailing list recently to address the ones he could find, but lacking a full audit, you probably shouldn't use any filesystem other than XFS.
Considering the gravity of these bugs, you might consider using XFS for everything, if the developers left these critical bugs in for so long, it makes you wonder about the general quality of the filesystems.

What of IBM's JFS? We run that here on our .75ish TB file server, and it's been great for us. We've not had any data corruption issues since we deployed it ~1yr ago, and it's survived a number of power outages with no problems. I'm impressed so far :)

See Tivos. If they use XFS, it's probably because it deletes even very large files instantaneously whereas most other filesystems takes longer the larger the file is. This is a clear advantage if you want to be able to delete a large movie file from disk at the same time that you want to record TV to that disk.

Summary for this thread :
Ideas for a Home Grown Network Attached Storage?

[...]I would like to build my own NAS and am interested in hardware/software ideas. While the small form factor PC cases are attractive, my NAS will dwell in the basement so I am thinking of a cheap/roomy ATX case with lots of power.[...]

Notice: this text is a mix of several authors plus personnal updates, I thank everyone. This time I tried to credit authors from /. crowd ;-)

General advice

One big growable partition: Take a bunch of disks, turn them into RAID5 array. Make a logical volume (LVM on Linux) and add the RAID-array to it. Create a growable device on the LVM and format with a standard growable FS.
When you get new disks simply create a new RAID5 array and add that to the logical volume and add to your current and grow the FS on it.

You don't want everything on one big RAID0, I lost 200G of data that way. I can say I'll never do that mistake again.

FileSystem type

Common linux file systems (ext, reiser, etc) contains critical data-losing type bugs on file systems bigger than 2TB, except XFS. This was found to be the case in even the most recent 2.6 kernels.
Tony Battersby posted a patch to the LBD mailing list recently to address the ones he could find, but lacking a full audit, you probably shouldn't use any filesystem other than XFS.
Considering the gravity of these bugs, you might consider using XFS for everything, if the developers left these critical bugs in for so long, it makes you wonder about the general quality of the filesystems.

What of IBM's JFS? We run that here on our .75ish TB file server, and it's been great for us. We've not had any data corruption issues since we deployed it ~1yr ago, and it's survived a number of power outages with no problems. I'm impressed so far :)

See Tivos. If they use XFS, it's probably because it deletes even very large files instantaneously whereas most other filesystems takes longer the larger the file is. This is a clear advantage if you want to be able to delete a large movie file from disk at the same time that you want to record TV to that disk.

Struture

There's no reason the NAS box has to have all the files in one file system. Just create multiple partitions or logical volumes. You export directory trees across the network on NAS, not file systems.

Exporting shares

I feel strange advocating a MS-originated protocol -- but the truth us, serving files via Samba on Linux is going to be the best-performing[1], most-compatible remote file system available. [1] Samba beats the MS implementations of SMB/CIFS. No guarantees about Samba vs NFS, GFS, Coda, whatever. Structure

There's no reason the NAS box has to have all the files in one file system. Just create multiple partitions or logical volumes. You export directory trees across the network on NAS, not file systems.

Exporting shares

I feel strange advocating a MS-originated protocol -- but the truth us, serving files via Samba on Linux is going to be the best-performing[1], most-compatible remote file system available. [1] Samba beats the MS implementations of SMB/CIFS. No guarantees about Samba vs NFS, GFS, Coda, whatever.

RAID or not RAID

Regarding RAID, it's been my experience working at The Archive that RAID is often more trouble than it's worth, especially when it comes to data recovery. In theory, recovery is easy, you just replace a bad disk and it will rebuild the missing data, and you're good to go. In practice, though, you will often not notice that one of your disks are borked until two disks or borked (or however many it takes for your RAID system to stop working), and then you have a major pain in the ass on your hands. At least with one filesystem per disk, you can attempt to save the filesystem by dd'ing the entire raw partition contents onto a different physical drive of same make + model, skipping bad sectors, and then running fsck on the good drive. But if you have one whopping huge 2.4TB filesystem, then you can't do that trick without a second 2.4TB device to dd it all onto, and even if you have that, it's probably going to be copied over the network, which makes an already slow process slower .. if you can stomach it, you might just want to make one filesystem per hard drive and NFS (or Samba, or whatever) export each of your six filesystems separately.

On the contrary:

Saying so about RAID is insane.
See mdadm/mdmonitor to get a mail as soon as there is a failure .
Personally I would recommend setting up nagios or some other software monitoring. Everytime something goes wrong on a machine, we write a script to monitor that. Now, very few things go wrong unnoticed.
I'd really much prefer that to not having a RAID array. We've used that system (*knock*,*knock*,*knock*), for 4 years, and with about 5TB of filesystems at work, we've never ever lost a RAID'ed filesystem. We have lost several, incredibly important filesystems that weren't RAID'ed.
If you have spare drives arround, you can configure mdadm to automatically add them into the system. Unlike the standard md tools, you can have one spare for any number of md arrays.

Beware of some misleading "advice": "RAID 5 is about as fast as RAID-0 on reads..." ok but "...the bottleneck on writes is the parity calculation, not access time for the drives." is false:
Even the paltry 366Mhz Celeron in my fileserver can perform parity calculations at nearly 1GB/sec. The bottleneck with RAID5 most certainly *is* the physical disk accesses (assuming any remotely modern hardware)
I would suggest using a motherboard with multiple PCI buses. Basically, look for something that's got two (or more) 64 bit PCI-X slots, as these boards nearly always have multiple PCI buses.
Also putting multiple IDE drives on a channel will destroy performance.
Using RAID50 instead of RAID5 is pointless.
Just buy yourself some four port IDE controllers, put one drive each port and use Linux's software RAID to create two four-disk RAID5 devices (or one 8-disk device if you prefer). Then put LVM over the top to make the space more manageable. If you've got the hardware resources, make sure each disk controller is on its own PCI bus, or at the very least sharing it with something inconsequential (like the USB controller or the video card)

External USB / FireWire enclosures

The state of external enclosures, USB chipsets and firewire chipsets is a sad thing.
I had to go through 3 different USB chipsets (different motherboards) before my external enclosure would write data without random corruption.
Firewire's no better, either. I had an Adaptec firewire card (Texas Instruments chipset, I believe) and it worked with my external drives, yet after 5 or 10 minutes, would randomly drop the drive and corrupt data.

Testimonial

I did this a while back. (3+ years, so it's obviousely not 1TB).
My fileserver runs 24/7 and has been doing that for about 3 years (minus downtime for moving).
I use 4 40GB SCSI drives in RAID 5 configuration, using Linux software RAID.(Obviousely I would have used large IDE now, but these were the cheapest per GB at the time, and I already had the SCSI controller laying around)
This gives me about 136GB of useable space. PArtition is running ext3 as filesystem. The CPU is a Pentium II 450 and it has 256MB of RAM. Is running on a Tyan dual mobo with builtin 10/100 and SCSI.
The server is running an older RedHat release with no GUI, upgraded to Kernel 2.6.8.1.
The RAID is shared on the network using Samba.
Read performance is decent, getting around 5-7MBytes/sec read speed which is pretty good on a 100Mbit link. Write speed is slower, around 3-5MB/s

Misc

When you're dealing with that much storage, you really need to catagorize your files into what needs to be backed up and what doesn't.
If you use Linux, LVM will become your new best friend. Think of: noise and power use, heat and airflow

Don't forget to enable S.M.A.R.T. drive monitoring
I do a lot of software raids and with smartctl, no drive crash has ever surprised me. i always had the time to get a spare disc and replace it on the array before something unfunny happened.
do a smartctl -t short /dev/hda every week and a -t long every month or so ...
read the online page of it: http://smartmontools.sourceforge.net/
Software raid works perfect on linux... and combined with LVM the things gets even better
A number of people also recommended MDADM [freshmeat.net] for building and maintaining software RAID systems on Linux.

This won't be best solution noise-wise, but this would extend the drive lifetime. Cut extra holes to the case and build air-flow tunnel to help cooling the drives. I measured drop from 46C to 25C with 12cm nexus low speed fan.

Some small commercial solutions

Device for Samba sharing a USB drive 100$
Need to add: USB drive or drive + USB adapter, up to 8.

Rebyte 150$
A simple flash Linux distro with a converter board that plugs in to an IDE slot. Supports all the standard raid setups. I recommend investing in cooling for hard drives -- not things you want to have fail on a NAS system.

Credits:

Hast zoeith GigsVT HoneyBunchesOfGoats sarahemm booch richie2000 -dsr- Keruo TTK Ciar ComputerSlicer23 drsmithy delus10n0 tchuladdiass Winter beegle

*** advid.net Conclusion ***

Some small commercial solutions are worth to look at -for the lazy/hurried, but a real DIY setup would be:

ATX PC tower with linux 2.6 distro and the kind of disks you can aford (ATA,SATA,SCSI), low or medium RAM and CPU are enougth, and a 10/100 NIC of course. Better perf with one drive per chanel
#1 Use software RAID5 (raidtools2 or mdadm) and LVM.
#2 One or more logical volume.
#3 A growable filesystem (XFS (lnk2), JFS (lnk2), ext3, ext2
#4 A reliable filesystem (XFS, JFS, stable ext3 ? or good old ext2 ?)
#5 Export shares with Samba.
The box: since NAS could be outside the rooms you live, add extra holes and fans to keep the disks cool. Power: UPS here of course.

Please can you comment about:

#1 Some pointed out that raid could be worse than no RAID but simple copies from one disk to another, I'm thinking of rsyncing locally or even to some other host on LAN when reachable. What do you think ?

#2 Different logical volume for different kind of files (size, lots of writes or mainly reads, backup needs). Thus we would choose the FS and tune it differently on each volume. From backup point of vue it could be simpler and smarter: think of a small FS with your most precious files (your work), it could be handled in a 1st class way (replicas,multi backup everywhere,...). What do you think ?

#3 & #4 Some more feedback for XFS, JFS, ext3, ext2 on kernel 2.6 ?

Edit 1.1:

I think ZFS from Sun is the best FS for this purpose, too bad it can't be on Linux... yet.

Rev 1.1

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Running a Server at Freezing Temperatures (slashback)

advid.net advid.net writes  |  more than 9 years ago Summary of this thread:
Running a Server at Freezing Temperatures
As a part of a backup solution, I'm thinking of running a backup server in my unheated, unattached garage [...] the temperatures very often drop below zero degrees Celsius.

Notice: this text is a mix of several authors plus personnal updates, I thank everyone

Hard drive

Lubricants become more viscous at low temps:
if it got really cold, the lubricants in the drive spindle could actually become solid, freezing the bearings and burning out the motor.
Tell your PC to never turn off hard disks, never turn off fans. (might freeze if they stop, and not start again).

Thermal expansion of the platters:
Hard drive platters go through a normal amount of expansion because solids expand when heated and contract when cooled. Drive controllers are designed to recalibrate occasionally to check for expansion, to insure the heads are positioned correctly, off-track positioning leads to errors. But I seriously doubt the calibration would work outside the range of temps designed into the controller.

Case

Make sure your case is hardened. Every little critter, including mice, will want to live in the warm case. We had a computer in an astronomical observatory dome and mice built their nest on the CPU. The acid in urine from the mice destroyed the motherboard.

Get a case with a thermostatically-controlled main fan (not CPU fan, main fan). Put this in a 5-sided wooden box (hardened against critters, screened on the bottom) and insulate it with construction foam (inside) on four sides and the top. Half-inch foam will probably do. Vent the system fan out the bottom.
What this will do is create a "bubble" of warm air inside the box that is vented when the fan is running and stable when it is off. This will keep your box temperature roughly even. If you are concerned about cold-starting hard disks after a period of off-time, make sure you have a power supply which remains off after a power loss and add a 100 W light bulb inside the box. When you want to power the system back on, switch the bulb on and leave it for an hour or two before you hit the power button, then turn the bulb off again. Do not bring cold hardware into a warm, humid house to warm up - you will get condensation.

Take the floppy out of the machine, and replace the hole in the front with a blank panel. It might be a good idea to do that with the CD/DVD drives as well. Make sure that the back of the case is all sealed up, (ie, no open holes for old PCI devices you no longer have). Lastly, Don't put anything over or close to it. Your going to need it to be able to suck in air, and evacuate the air with the fans.

Misc

Some positive feedback for running such a server at 5C without any problem.
Mind the capacitors min temp specs.

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Software Survival Kit (slashback)

advid.net advid.net writes  |  about 11 years ago Summary of this thread:
What Would You Put Into A Software Survival Kit?
Plus personal updates

Systems

  • Win98SE
  • Your prefered Linux Distro
  • WinNT4
  • WinXP

Bootable media

  • TOMSRTBT
  • Win98SE Boot Disks
  • Ghost bootable floppies set
  • Knoppix
  • QNX Demo, both modem & lan Disks
  • DOS 6.22 disks
  • any Linux rescue disk/CD

System Tools

  • Partition Magic
  • Norton Ghost
  • The new FDisk for large partitions
  • LapLink, FastLynx http://www.sewelld.com/FastLynx.asp FastLynx has the advantage that it can transfer files between XP and say DOS or Linux, over Serial, Parallel, or USB
  • Delpart.exe
  • McAfee Virus Scan, command line version
  • Antivirus. http://www.free-av.com, F-Prot http://f-prot.com
  • Norton Utilities
  • Hard disk checking utilities (from Maxtor, Seagate, etc) PowerMax http://www.maxtor.com/en/support/downloads/powermax.htm , SeaDiag, HDDiag, WD Lifeguard
  • Memtest86, http://www.memtest86.com/
  • DosDiag - for checking your hardware; http://www.5star-shareware.com/Utilities/Diagnosti cs/bcm-diagnostics.html
  • Favorite tools from Sysinternal/Winternals: FileMon,RegMon,PsTools, ... ERD, NTFS DOS Pro
  • BPR, disk & partition recovery, http://www.data-recovery-software.com/
  • Offline NT Password & Reg Editor, http://home.eunet.no/~pnordahl/ntpasswd/
  • F.I.R.E. (Forensic Incident Response Environment) Linux + security tools, http://fire.dmzs.com/?section=faq
  • ? SpinRite http://grc.com/spinrite.htm
  • ? Lavasoft Adaware

User Tools

  • Undelete. A good and free version can be found at http://home.arcor.de/christian_grau/rescue/
  • ZIP, RAR, ACE. Bzip2 and gzip for DOS or Win32
  • UltraEdit
  • ? XTGold 2.0 or 2.5 - runs on DOS
  • ? XTree Ztree www.ztree.com

Misc Apps & Files

  • Acrobat Reader, Quick Time, Flash/ShockWave
  • Nero Burning Rom
  • misc drivers for personal hardware and common nomad devices
  • MS Service Packs (OS/Office)
  • Standalone Web Browser ( OffByOne, others ... )
  • PowerDVD, PaintShopPro
  • Microsofts free Word and Excel viewers

HardWare related to OS installation

  • Blank Diskettes
  • Screwdrivers
  • Spare screws
  • Spare IDE cable
  • Spare jumpers
  • Spare IDE drive or external drive
  • RJ45 cross over CAT-5 cable
  • Laplink Cable
  • RS 232 cross over serial cable

Links

  • List of rescue disks: http://plug.twuug.org/articles/rescuedisk.html

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