Author: Mike Talon

Is that drive really bad?

Feb
22
2012

External hard drives can be funny things. Sometimes, they’ll throw up errors for no apparent reason, and sometimes those reasons – though not immediately apparent – will destroy your data.

So how do you tell the difference between the occasional USB connection hiccup and the imminent failure of a hard drive?

Natively, it’s a bit difficult, but doable. Internal drives have S.M.A.R.T. monitoring software, but USB drives can rarely use that form of monitoring, so troubleshooting is much more complex. All Mac OS installations have a suite of disk tools installed by default in the Utilities folder, and you can start there.

In the Utilities folder, open Disk Utility and click the hard drive in question in the left-hand column. Note that there are disks and volumes. Disks are hardware devices that hold volumes. Volumes are sections of a disk that contain data. Even when you’re creating a disk with only one volume, it still holds a volume (the volume just takes up all useable space on that disk).

Once you click on the disk, you’ll notice that most of the right-hand section of Disk Utility is greyed out, but the key tools are available here. Click First Aid, and then click Verify Disk. This will do a check across the disk to make sure that there are no major errors, and report back if everything is ok, or something looks wrong.

If you do find some issues, you can try using Repair Disk to fix them. If the error is logical (i.e. not a physical fault on the drive itself), this option can often fix the problem and get you back to normal. As always, try to back up everything off the drive before you begin. Repair Disk is meant to be as non-invasive as possible, but it can and WILL overwrite data if it finds errors.

If the Verify comes up clean, but you’re still having problems, then there could be a physical issue going on. They come in two flavors: minor hardware hiccups and bad sectors/blocks.

Hardware hiccups can be caused by a lot of things. Check that the power supply is firmly plugged in first. I know this sounds stupid, but you’d be amazed how many times I thought an external USB drive was dying, but in reality it was just that the power cable came loose and was shutting off the drive every few minutes.

Also make sure that all cables are security seated both at the drive and on the Mac itself. I have found on more than one occasion that a USB cable worked itself lose at either the drive or hub end. Of course, checking to make sure the USB hub is working – if you use one – is also a good idea. Try plugging other devices into the hub and looking for errors or problems.

If the hardware seems ok, but you still have issues, then it’s possible that a block or sector on the drive has gone bad. This is rare these days, as most internal and external drives will automatically mark a bad sector and simply not use it anymore, but bad sectors/blocks can indeed still cause havoc if the drive doesn’t – for whatever reason – realize they’re actually bad.

Try copying everything from the drive to another drive or set of drives if you can. If there is a bad block or sector, this process will result in the drive un-mounting itself with no warning. Power the drive off and back on, and move on to the next section. If that process works, copy everything back to the drive. If both operations succeeded, but you still get other odd behavior or other problems, then the drive is most likely failing and should be replaced.

If you do have a bad block or sector and the system dropped the drive but it came back online, you may need a new drive, but there’s still a chance you can get around it. Back up everything you can off the drive. I can’t stress that enough, because we’re about to wipe the thing clean. Copy everything you possibly can off of the disk to other storage before proceeding. That means copying everything you can off ALL volumes on that hard drive, even those that seem ok. You have been warned.

Back in Disk Utility select the drive (not the volume) that you want to attempt to fix. Go to Erase, and near the bottom click the Security Options button. Move the slider to the first position away from “Fastest” on Lion, which will show text stating that the system will write zeros over all data on disk. On Snow Leopard, chose the Zero Out or 1-Pass option. Click OK.

Click the Erase button, and read the warning that comes up carefully! This will totally destroy all data on the hard drive, and consumer data-recovery tools will be unable to get it back. Make triple-sure you have the right drive and that you backed up everything you could.

As the Erase operation goes through the process, it writes zeros to each bit on the disk. This will force any bad blocks and sectors to be recognized on write, and hopefully flagged as bad so they won’t be used anymore.

If that process works without errors, then you can use the disk again. If the Erase operation fails, then the disk has indeed gone bad, and must be replaced.

Since disk errors can happen without warning, keeping regular backups is the only true way to be sure you can always get to your data. If there is a problem, you can troubleshoot, but sometimes disks die, and only a backup can get you back up and running.

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What is CAPTCHA?

February 22, 2012

By Mike Talon
in Security
No Comments

Spam is a major issue on social networks, blogs and forums these days. Spammers have even resorted to hiring “human bots” to troll websites and post comments and postings just to get their site links a bit higher on search engine results.

To try to combat the problem, many sites have resorted to CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart). This technology is simply the use of some manual test that a human being would have no issues passing, but a computer would be unable to complete correctly.

Generally speaking, the test takes the form of a series of letters and numbers that are rendered as a graphic (like in the picture above). A human has no issue typing the letters on the screen, but a computer can’t, since the computer only “sees” the image as an image, not as a series of characters.

The test gets its name from the work of Alan Turing, a computer scientist who spent a great deal of his life trying to figure out if a machine could ever think exactly like a human. The result of that work helped win World War II (he helped build the Ultra machine used to break the German ENIGMA code generator system); and also helped create a series of tests to see how “human-like” machines could get.

The so-called “Turing Test” is still used today against advanced computer systems. A human operator sits in an isolated room and sends a series of questions to both another human and to a computer. The operator then tries to determine which is the human and which is the computer based on the reactions, responses and answers they get from both subjects. If the operator cannot correctly identify the computer, it is said to have passed the test.

And so, in order to try to weed out automated computer systems trying to post spam to blogs, networks and forums, tech professionals often implement CATPCHA tests to block them.

While the idea is great in theory, the benefits to CAPTCHA are severely limited by several factors these days:

– Spammers are hiring human beings in depressed economies to answer CAPTCHA tests and post nonsense to forums and blogs, bypassing the test for a few cents per dozen posts.

– People with visual disabilities (such as being legally blind or color blind) have issues passing the tests. This is either because the CAPTCHA provider didn’t include an audible test with the visual one, or because the CAPTCHA itself is in non-contrasting colors that are difficult to read for someone who is color blind.

– The CAPTCHA’s themselves have become so intricate and complex that real humans can’t answer them correctly either. I’ve seen math problems, characters so twisted around they’re unreadable, so many intersecting lines that you can’t read the characters, etc.

– Computer systems are getting complex enough that they can actually pass the CAPTCHA.

While you will still see CAPTCHA on many websites, and while they still have some use in the overall war on spam, you should probably avoid forcing a CAPTCHA test for your blog or website.

Instead, require administrator interaction before a blog comment can go live, require registration before a forum can be posted to, and use other techniques that will help keep spammers away from your postings. Many content management systems (such as WordPress) allow you to permit those who’s comments you have allowed in the past to post without having to get permission each time; for example.

If you find a CAPTCHA that is unreadable, unusable, or both; let the site administrator know that they need to fix it or remove it.

Photo Credit: plindberg

Lock it Down!

February 22, 2012

By Mike Talon
in Security
No Comments

Your Social Media identity is your brand, your representation online. You should be protecting it just like you protect your wallet, keys and everything else you don’t want people playing with without your permission.

Basic Social Media security isn’t very hard to accomplish, doesn’t diminish your ability to get things done, and doesn’t take a lot of time to keep up with. It’s also free for the most part, so it won’t even make a dent in your wallet if you only need the basic features.

For social networks and bookmark/photo sharing sites, you can do three things to help ensure you stay safe:

– Choose a password that’s not a word in the dictionary, is made up of letters and numbers, and it at least 8 characters long. XKCD had a great way to do that. You can also simply pick a phrase that you’ll remember, and translate that into a combination of letters and numbers.

So “To Infinity, and Beyond!” becomes “2InfinityAndBeyond!” If the network in question doesn’t allow punctuation in passwords, just drop the “!”

[editor’s note] PLEASE don’t use that one as your password, as anyone reading this article will be able to get into your social networks if you do.

– Make sure you know what’s connecting to your networks. Twitter, Facebook, LinkedIn and others have Connections, Applications and/or Privacy pages that detail what apps can see and use your data, and what data they can see and use. These pages are typically on the Settings, Options, or Privacy pages for your account once you log in. Be sure you know what each application is, what it does, and how it accesses/uses your information. Remove any apps you no longer use, or don’t want to use, and whenever possible, limit the apps you do use just to the vital data they require and no more.

– Try to never use social networks on computers you don’t own. While it’s probably impossible to always follow this rule, do it whenever possible. If you must use a social networking site on a computer you don’t own, make sure the “remember me” or “always keep me logged in” checkboxes are cleared and make sure you log off the social network site when you’re done, don’t just close the web browser or window. Public computers – like at libraries and internet cafes – are prime targets for key-tracking malware. Use them for social networks (or really anything that requires you to log in) as an absolute last resort.

For blogs, things get a little trickier:

– Do use secure passwords, just like for social networks. Make sure they are NOT the same passwords you use for social network sites.

– Keep your blog updated. If you use WordPress, for example, check weekly for new updates both for the WP software and for any plug-ins and themes. WordPress 2 and up will allow you to update these items with a few clicks, so there’s no excuse for not staying updated. If you are with a hosted blog provider like Blogger, then the host will typically do this updating for you, but it never hurts to check your Settings/Administration pages just to make sure.

– Use a 2-factor authentication system if you host your own blog. Duo Security has a free version of their smartphone-based authentication system that works great with WordPress, for example. This ensures that just because your password is breached, there is another layer of security for most forms of blog access to help ward off attackers.

– Moderate comments. This isn’t so much for your direct security as for spam prevention and keeping links to malware-infected sites off your Comments page. Moderation is a bit annoying at times, but you can minimize that by setting up an account with a filtering service, like Akismet, to remove the obvious spammers and only bug you when a comment appears legitimate.

Take a few steps today to help close the loopholes that allow attackers to get hold of your Social Media info and sites. An ounce of prevention now helps avoid weeks of clean-up later.

Photo Credit: Dazzie D

Dealing with the Negative: Part I – Is It Really Negative?

February 22, 2012

By Mike Talon
in General Info
No Comments

Into each blog, several trolls must fall. This is an immutable law of the Internet, and you should be ready to deal with negative posters, bloggers, tweeters, etc.

The first step in dealing with the haters is to identify which ones are real, and which ones are just annoyances that you can’t and/or shouldn’t do anything about.

For example, let’s say that someone is tweeting something negative about your company. Are they someone you should be concerned about, or is it just a spammer who happens to have latched on to your company name in their spam?

First, determine if the threat is real:

1 – Does the tweet/post/blog seem to actually have an issue with your company or product? You can usually tell because the real people with issues state them clearly and distinctly. “Your product broke and caused something to happen” is more likely to be legit than “Have you heard how bad Product A is?”

2 – Is the poster a real person, or a spammer looking to get visibility by leveraging your product? Spammers will simply post things like “Comparison of Product X and Product Y” with a link to an article that has nothing to do with the poster. In all likelihood, the page they link to may not even be a real comparison or legitimate document, but rather a site full of advertising (or worse, a malware trap site).

3 – Is the issue something you can fix, or just someone airing their opinions? Many times, users spout off about a gripe, but have no intention of actually working to fix the problem. Gauge their reactions to your responses to see how you should continue – or if you shouldn’t continue.

Often, you can find out the answer to all three of these questions by sending a simple @Reply, Comment, etc. that says “Hi, I work for Company A, and we’d like to help.” Avoid using direct messages, even if they follow you, as the idea here is to publicly show everyone else that you’re responsive to negative tweets/posts/blogs. After all, if you can’t help this one person, you want the rest of the world to see that you at least tried.

If the poster in question replies back that they want help, then you have a legitimate user who is frustrated, but one you can work with. If, on the other hand, the poster either doesn’t reply back, or worse they continue to stream abuse, then it would be better to classify them as “unreachable.” At that point, keep an eye on them, but don’t engage them directly. All you’ll do is give them more fuel, and they’re not going to come around to your point of view anyway.

The idea is to find those people who are truly frustrated and looking for help, but to not “feed the trolls” and contribute to the noise level online without getting anything out of it for you and your company.

Next week, we’ll discuss what you can do both in cases where the negativity is real and the person is willing to accept your help; and then those cases where the comments/posts are real, but the user has a bias against your company and does not want help.

Photo Credit: jurvetson

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