New Webinar on How to Design Open Source Databases for High Availability

Join us March 27th for this webinar on how to design open source databases for high availability with Ashraf Sharif, Senior Support Engineer at Severalnines. From discussing high availability concepts through to failover or switch over mechanisms, Ashraf will cover all the need-to-know information when it comes to building highly available database infrastructures.

It’s been said that not designing for failure leads to failure; but what is the best way to design a database system from the ground up to withstand failure?

Designing open source databases for high availability can be a challenge as failures happen in many different ways, which sometimes go beyond imagination. This is one of the consequences of the complexity of today’s open source database environments.

At Severalnines we’re big fans of high availability databases and have seen our fair share of failure scenarios across the thousands of database deployment attempts that we come across every year.

In this webinar, we’ll look at the different types of failures you might encounter and what mechanisms can be used to address them. We will also look at some of popular high availability solutions used today, and how they can help you achieve different levels of availability.

Sign up for the webinar

Date, Time & Registration

Europe/MEA/APAC

Tuesday, March 27th at 09:00 BST / 10:00 CEST (Germany, France, Sweden)

Register Now

North America/LatAm

Tuesday, March 27th at 09:00 PDT (US) / 12:00 EDT (US)

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Agenda

  • Why design for High Availability?
  • High availability concepts
    • CAP theorem
    • PACELC theorem
  • Trade offs
    • Deployment and operational cost
    • System complexity
    • Performance issues
    • Lock management
  • Architecting databases for failures
    • Capacity planning
    • Redundancy
    • Load balancing
    • Failover and switchover
    • Quorum and split brain
    • Fencing
    • Multi datacenter and multi-cloud setups
    • Recovery policy
  • High availability solutions
    • Database architecture determines Availability
    • Active-Standby failover solution with shared storage or DRBD
    • Master-slave replication
    • Master-master cluster
  • Failover and switchover mechanisms
    • Reverse proxy
    • Caching
    • Virtual IP address
    • Application connector

Sign up for the webinar

Speaker

Ashraf Sharif is System Support Engineer at Severalnines. He was previously involved in hosting world and LAMP stack, where he worked as principal consultant and head of support team and delivered clustering solutions for large websites in the South East Asia region. His professional interests are on system scalability and high availability.

via Planet MySQL
New Webinar on How to Design Open Source Databases for High Availability

Now you can visit Disney Parks in the US through Google Street View

Special for kids — and importantly parents of kids — now you can get designs on visiting Disney — and dropping a small fortune in the process — thanks to Google Maps after it added Street View images for 11 Disney Parks.

The feature looks to cover parks in the U.S. only at this point, but that alone might help you relive a recent visit, or else familiarize yourself for the first/next one.

It’s been interesting to watch Google Maps develop into a tool for tourism. Particularly in Asia, governments and tourism boards have worked with Google to help bring popular destination and cultural landmarks onto the service. That’s in contrast to the West, where Maps had been seen as a service that poses significant privacy concerns — remember back in 2010 when Google sucked up personal data via its Street View cars?

Disney might not be a world wonder or cultural hotspot, but it definitely makes sense for the parks to have a more visual presence on Google Maps, and so here we are.

Don’t worry, trusted sources close to TechCrunch’s Matthew Panzarino have assured me that he will continue to make his annual visit to Disneyland to test Apple’s newest iPhone in real-world conditions despite this new tie-up with Google. Some things just can’t be digitized.

via TechCrunch
Now you can visit Disney Parks in the US through Google Street View

Google adds Disney parks to Street View

Last year Google revamped its Street View cameras to help us better map the real world, now it’s taken the technology to a much more magical land. From today, you’ll be able to explore inside 11 Disney Parks, getting an on-the-ground glimpse of all its castles, rides and attractions, including the captivating Avatar-themed world of Pandora. It’ll also definitely prove popular when the Star Wars area opens up next year. Now if only the imagery was available in real time, so we’d know whether to bother lining up for Splash Mountain or not.

via Engadget
Google adds Disney parks to Street View

Researchers: Schools are safer than they were in the 90s, and school shootings are not more common than they used to be

by Allie Nicodemo and Lia Petronio

The deadly school shooting this month in Parkland, Florida, has ignited national outrage and calls for action on gun reform. But while certain policies may help decrease gun violence in general, it’s unlikely that any of them will prevent mass school shootings, according to James Alan Fox, the Lipman Family Professor of Criminology, Law, and Public Policy at Northeastern.

Since 1996, there have been 16 multiple victim shootings in schools, or incidents involving 4 or more victims and at least 2 deaths by firearms, excluding the assailant.

Of these, 8 are mass shootings, or incidents involving 4 or more deaths, excluding the assailant.

“This is not an epidemic”

Mass school shootings are incredibly rare events. In research publishing later this year, Fox and doctoral student Emma Fridel found that on average, mass murders occur between 20 and 30 times per year, and about one of those incidents on average takes place at a school.

Their research also finds that shooting incidents involving students have been declining since the 1990s.

Four times the number of children were killed in schools in the early 1990s than today, Fox said.

Click here to read the entire article at news.northeastern.edu.


via Buckeye Firearms Association
Researchers: Schools are safer than they were in the 90s, and school shootings are not more common than they used to be

Why Gun-Control Fails Miserably

Recently, National Review‘s David French penned an op-ed in hopes of explaining to some people why so many of us own guns. Yesterday, Bethany Mandel did the same thing in the pages of the New York Times. The idea was simple and noble. They wanted to show folks who don’t own guns why so many others do.

French notes that the response to both articles illustrates why gun control fails so miserably every single time.

Yet the responses to both essays have helped demonstrate why the Left keeps losing on guns. It simply can’t persuade a rational, reasonable adult who’s experienced a threat that they’re safer without effective means of self-defense. Indeed, the effort to make this case is so often rooted in condescension or ignorance that it’s deeply alienating.

First, there’s an odd argument that it’s somehow illegitimate to make a decision based on “fear.” Or — as one correspondent put it — “fear and paranoia.” This makes no sense. Americans make safety-based decisions all the time. Is it wrong to buckle a seatbelt because that’s a “fear-based” decision? Should you ride a motorcycle without a helmet just to show the world you’re not scared? Reasonable people take precautions in the face of real threats.

Next, you immediately hear that you’re foolish. That “you’re more likely to hurt yourself than defend yourself.” In other words, the gun is more dangerous to you and your family than it is to any given criminal. But if you’re speaking to a responsible, non-suicidal adult, then this argument is flat-out wrong. In fact, even when you include suicides in the analysis — and compare them to the best estimates of annual defensive gun use — you’ll find that law-abiding Americans use guns to defend themselves far more than they do to hurt themselves.

Moreover, another person’s irresponsibility is irrelevant to the existence of my fundamental liberties. I don’t surrender my free-speech rights because another person uses theirs to troll Twitter. I don’t surrender my right to free exercise of religion because another person joins a cult. I don’t surrender my inherent and unalienable right to self-defense because a man across town decides to kill himself.

It’s part of a much larger post, and I highly recommend you read it, but he’s right.

Many other people and I find the arguments against having the means to defend yourself delusional. I’ve heard them all before, but they’ve never made any sense. How am I more likely to hurt myself than defend myself? I’m not an idiot, after all, so if I follow a few basic safety rules, I shouldn’t have a problem, right?

Yet in the mind of the gun control activist, it seems we’re all perpetually stupid. No one can comprehend the basics of gun safety, which is probably why the words “gun safety” coming out of their mouths should be translated as “ban them all.” They think that’s the only way to keep any of us safe from guns.

The problem for them is that we don’t need them. Most Americans, even those who don’t own guns, know that we don’t need them. They can look at these arguments and see them for what they are, complete and utter nonsense.

That’s why gun control doesn’t work. It doesn’t work because it’s always premised on people being too stupid to live without some elite telling us how to do it.

No one wants to put up with that, so even a lot of non-gun owners refuse to accept that line of reasoning.

Yeah, they make a few wins here and there, but they’re small potatoes, and they can’t do it on the national stage. To make matters worse, they know it, and it burns them up.

It just makes me giggle.

via Bearing Arms
Why Gun-Control Fails Miserably

Netflix will let parents block individual movies and shows

Netflix announced today that it will soon be rolling out a new tool for parents. Already, parents can manage what their kids watch by putting all content above a particular maturity level behind a PIN or by marking which accounts belong to a child. But soon, parents will also be able to require a PIN for certain shows or movies. This way, parents won’t have to block full levels of content if they don’t want to and can instead just keep their children from watching certain titles. Additionally, maturity level ratings will also be displayed more noticeably on the screen when a new title begins playing.

Netflix’s changes come as a number of companies are working to make their platforms more child-appropriate. Apple plans to introduce more parental controls to its devices in the near future and YouTube recently had to deal with some disturbing content that was parading as kid-friendly. Gadgets geared towards children have also come under scrutiny as privacy concerns mount and Facebook’s new Messenger Kids app has attracted criticism for encouraging kids to spend more time on digital devices.

Netflix says its new controls will be rolling out in the coming months and that it’s also looking into how to make maturity level ratings more descriptive and easier to understand.

Via: VentureBeat

Source: Netflix

via Engadget
Netflix will let parents block individual movies and shows

Activate Netflix’s New Parental Controls

Parents worried their kids will consume some unseemly content on Netflix have been able to block all the content that falls under a particular rating. Now, Netflix’s latest update gives you a little more control, allowing you to prevent your young viewer from watching particular programs you deem unsuitable for them, even if it falls in your selected ratings range. Not everyone wants their kid watching Stranger Things, no matter how many games of D&D they play. To keep them away from questionable content, all you need is a PIN and a list of movies you don’t want your child to see.

Add a PIN, Add Some Banned Movies

Go to Netflix to visit your account page and select the Parental Controls link. Enter your password and choose a PIN, which you’ll need to unlock the restrictions should you want to watch a previously restricted title. From there you can drag the rating slider from “Little Kids” to “Adults” and restrict by maturity level. If you just want to restrict a few particular movies and don’t want to put an entire category of films off-limits, you can add the name of the show or movie you want to block under the Restrict Specific Titles section.

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Netflix also made it easier to figure out a movie’s rating before that first channel-changing scene. Now, when you start a show, you’ll see the film rating prominently displayed in the corner. Reconsidering your viewing ban on a few programs? Just enter the PIN when you select the banned title.


via Lifehacker
Activate Netflix’s New Parental Controls

Paul Allen team locates another long lost warship as USS Lexington is found 76 years after sinking

USS Lexington
A 5-inch gun on the USS Lexington as it is seen at the bottom of the Coral Sea, off the coast of Australia. (Vulcan Photo)

A team led by Paul Allen has done it again at the bottom of the sea, locating the wreckage of another long lost U.S. Navy warcraft.

A crew working with Allen’s Research Vessel (R/V) Petrel found the USS Lexington on Sunday, 76 years after it sank in the Coral Sea, more than 500 miles off the eastern coast of Australia. The aircraft carrier — one of the first ever built in the U.S. — was located about two miles below the surface.

According to a post on the Microsoft co-founder’s website, the ship, which went down with 35 aircraft on board, took part in the Battle of the Coral Sea from May 4-8, 1942. The Lexington was hit by multiple Japanese torpedoes and bombs, in a battle alongside the USS Yorktown and three Japanese carriers. A secondary explosion and fire ultimately led to calls to abandon ship, and 2,770 crewmen and officers were rescued, while 216 were lost.

The USS Phelps delivered torpedoes that sank the crippled ship, the first aircraft carrier casualty in history.

“To pay tribute to the USS Lexington and the brave men that served on her is an honor,” Allen said in a statement. “As Americans, all of us owe a debt of gratitude to everyone who served and who continue to serve our country for their courage, persistence and sacrifice.”

USS Lexington
The USS Lexington off Honolulu, Oahu, Hawaii, with Diamond Head in the background, on Feb. 2, 1933. (U.S. Navy Photo)
USS Lexington
Damage is shown to the port forward 5-inch gun gallery on USS Lexington during the Battle of the Coral Sea, May 8, 1942. The view looks aft, with the ship’s number two 5/25 gun in the foreground, still manned and in operation. The number four 5/25 gun is immediately beyond, trained out to port and aft. (U.S. Navy Photo)

Robert Kraft, director of subsea operations for Allen, said that the ship was on a priority list of those lost during World War II.

“Based on geography, time of year and other factors, I work together with Paul Allen to determine what missions to pursue,” Kraft said. “We’ve been planning to locate the Lexington for about six months and it came together nicely.”

Underwater images and video taken by a subsea vehicle launched by Petrel show the large guns on the carrier as well as some of the airplanes resting on the ocean floor. The Petrel’s state-of-the-art subsea equipment allows it to dive to 6,000 meters, and since being deployed last year it was active in several missions in the Philippine Sea before moving to the Coral Sea.

Last year, Allen-led expeditions led to the discovery of the USS Indianapolis and USS Ward, as well as the Italian WWII destroyer Artigliere. In 2015, the USS Astoria and Japanese battleship Musashi were located.

Check out more images of the Lexington site, released by Allen’s team on Monday:

USS Lexington
The USS Lexington nameplate. (Vulcan Photo)
USS Lexington
An aircraft on the bottom of the Coral Sea. (Vulcan Photo)
USS Lexington
A blast shield is shown, with writing, on the USS Lexington. (Vulcan Photo)
USS Lexington
The control room onboard Paul Allen’s R/V Petrel. (Vulcan Photo)

via GeekWire
Paul Allen team locates another long lost warship as USS Lexington is found 76 years after sinking

Experimenting with Turning an Ultrasonic Cleaner into an Ultrasonic Knife

This video from the YouTube channel, This Old Tony, is one of the most inspiring I’ve seen in a while. Which is kind of an odd thing to say since the results are something of a fail. Or are they?

Tony was fascinated by his ultrasonic cleaner. He wanted to learn more about how it works and was curious to see if he could re-direct the soundwave hardware in such a cleaner to do something else useful. So, he bought a smaller $60 cleaner to take apart and to better understand its inner workings. He takes us along for the ride.

With his newfound knowledge of how the cleaner and its hardware works, Tony decides to see if he can turn the unit into a ultrasonic cutting knife. He knows that the engineering of the horn will be crucial, but he doesn’t fully understand the acoustical engineering involved. No worries. He just tinkers towards his solution.

At one point, the video appears to end; the project a failure. But Tony comes back, presses on, and eventually comes up with something that actually kinda-sorta works. Proof of concept, anyway.

This video is a glorious example of the joys and value of tinkering. Tony’s curiosity led him to learning more about the inner workings of a tool he regularly uses, the underlying acoustical properties behind ultrasonic technology, and how an ultrasonic knife works. Tony also has a great low-key and funny presentation style which makes his videos fun to watch.

Not content to rest there (or leave his poor cannibalized cleaner alone to die with dignity), Tony decided to try turning the knife into an ultrasonic welder. Again, not a certifiable success, but the experiments are interesting and tantalizing. With more work, better engineering, and lots more futzing, it looks like you could possibly make your own ultrasonic hand tools.

via MAKE Magazine
Experimenting with Turning an Ultrasonic Cleaner into an Ultrasonic Knife

Things I Have Learned About Gun Control

One of the positive side-effects of the Trump administration is that citizens are far more informed on the issues than at any time in my memory. The public seems to be getting into the details on a lot of topics lately. Gun control is a great example. I consider myself under-informed on that topic, but improving daily, as are most of you who follow the news. And I thought it would be useful for some of you to compare your views on the topic to where I’ve evolved so far.

What follows is my public confession of ignorance on the topic. I will list the things I believe to be true, while asking readers to fact-check me. I’ll modify my list as corrections come in.

In no particular order, here’s what I think I know.

Gun control works. If it didn’t work, the Vegas shooter and the Florida school shooter would have used fully-automatic weapons and killed far more people. The one-time mass shooters are clearly using the most lethal weapons they can get without too much friction. Fully-automatic weapons are expensive, less available, and can create a paper trail with purchase. That’s evidently enough friction to make them not the weapon of choice. Therefore, the existing gun controls on fully-automatic weapons seem to work.

Professional criminals can always get weapons. But they are not the topic of most gun control conversations for that very reason.

States with tight gun control have lower gun violence. But those states are also blue states. The obvious correlation here is that liberals vote for gun control no matter how many or how few problems the state experiences. The state-to-state comparisons do not tell you if gun control works.

Comparing gun ownership in the United States to other countries is more misleading than illuminating because no two situations are alike. The United States isn’t Switzerland and it isn’t Japan.

Chicago has strict gun control and yet it has high gun violence. But that doesn’t tell you gun control doesn’t work. It might tell you Chicago is a blue (liberal) city with a gun violence problem. But that’s all it tells you. We can’t know if Chicago would have even greater problems without the existing gun laws.

Gun ownership is a safeguard against the government turning on citizens. While the professional military will always have overwhelming firepower compared to citizens, private guns would instantly be turned on the unprotected assets and family members of anyone involved in a coup attempt. That’s a safeguard.

The NRA opposes universal background checks for gun purchases because it creates a list of gun owners that would be useful for a government that might want to later confiscate guns. Yet the NRA itself is a list of gun owners, in effect. And any gun owner who buys a weapon, ammo, gun accessories, or uses a gun range is discoverable by their credit card or check purchases. If you subscribe to Guns & Ammo magazine, or visit gun websites, or say pro-gun things on social media, that’s discoverable too. So 98% (just a guess) of gun owners are already discoverable by the government.

There’s probably no practical way to effectively regulate or ban private person-to-person gun sales. But you could pass a law putting some liability (say a $10,000 fine for example) on the private seller in case the gun is used by the buyer for a crime within, let’s say, one year. Under this scenario, you also want to have legal ways to privately sell guns without the liability risk. That could include buying a one-year surety bond, or selling the gun to a licensed dealer. Just brainstorming here.

Gun owners worry about a slippery slope from background checks to gun confiscation. But with hundreds of millions of guns already in circulation, and a gun culture in our DNA, we already have Mutually Assured Destruction if the government were to attempt confiscation. The government itself would fall within a week, in my opinion. I judge the slippery-slope-to-confiscation argument to be a real risk, but a smaller risk than just about any other risk the country routinely discusses.

Politicians and citizens often refer to AR-15 rifles as assault weapons, or assault rifles. But a more accurate description, by far, would be “defensive weapon.” I would imagine that for every 10,000 AR-15 sales, perhaps one nut is buying for actual assault purposes. The rest are for sport shooting and defense. Words matter in political conversations.

According to at least one ER doctor who has seen many gunshot wounds, the high-velocity rounds of an AR-15 will explode organs and make wounds unsurvivable, whereas the typical lower-velocity handgun wounds often leave cleaner holes that can be less lethal. This generality assumes most handguns don’t have special rounds that could also explode organs. And distance from target makes a difference, I hear.

Gun owners say handguns are just as effective as AR-15s for mass shootings. This is clearly untrue for special cases such as the Vegas event where shooting distance was a variable. And I would expect human psychology to favor AR-15s for any “make me famous” killings such as the recent school tragedy. I hate to say it, but a military-looking weapon is going to be more appealing, and feel more dominant, for such killers. It would also be an advantage over police on the scene if the first responders had only handguns and shooting distance is a factor. So while it is true that handguns can produce mass casualties, and have, it is also probably true that access to AR-15s raises the risk of mass shootings and the death count too. No one can estimate how much of a real difference it would make. My best guess is “some,” but a small improvement might be enough to matter.

Gun owners say gun control doesn’t work because any law can be skirted. You can’t plug all of the holes in the system. But gun control doesn’t attempt to plug every hole. It attempts to add some useful friction in places that might improve things by 2%, for example. When it comes to life and death, small improvements count.

Some people tell me there are already universal background checks in the law (and therefore existing lists of gun buyers) but I assume that system is incomplete or we wouldn’t be discussing it. I could use some fact checking there.

If universal gun background checks are objectionable to the NRA, would a no-buy list also be objectionable? A no-buy list also carries the risk of identifying legal gun buyers simply because you have to do a search with the buyer’s name to know if he or she is on the no-buy list. But maybe we could mitigate that risk by designing a system that automatically sends a thousand random names of real people with every query so the government can’t tell who the search was for. The gun store owner would get back only the no-buy names from the thousand, in alphabetical order, so it would be easy to check if the customer in front of you is one of them. Or perhaps the gun story owner can see a list of no-buy people in the buyer’s zip code so no query with the buyer’s name is ever used. Just brainstorming here. Might be other solutions that are better.

I will correct and update this list as I learn more on the topic. How close is my understanding to yours? Let me know in the comments or on on Twitter at @ScottAdamsSays.


I started a Patreon account so my audience can influence my content — via micro-donations as low as one dollar.

Writing about persuasion and politics reduced my income by about 30-40% because of tribal effects. I took that risk with full understanding of the outcome because I thought it was worth educating the public on what they were witnessing.

Patreon funding will persuade me to express my opinions as often as practical without worrying about the sensibilities of sponsors, advertisers, or corporate bosses. I appreciate all of you who are making this happen.

 

 

 

The post Things I Have Learned About Gun Control appeared first on Dilbert Blog.

via Dilbert Blog
Things I Have Learned About Gun Control