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A PDA or a Tiny Server?

Posted on May 26th, 2010 by Victoria Pal in Tech

I previously owned an Acer N50. By modern standards the PDA is outdated. When I sold it the first thing a teenager asked me was "Is the mobile phone in it working OK?" Sadly, no, it does not have a mobile phone in it. It's that old now. Despite that fact, it was a great PDA when it was released and still got a lot to offer 4 years later.

Two of its functionalities really gave the Acer N50 a purpose in present times. First of all, it had a USB host function. Not common for pocket PCs in 2005 and still not part of many handheld devices nowadays. This function alone enabled the device to recognize several other devices, such as USB sticks and generally all available USB hardware (well, if drivers are present). In addition, WiFi reception was pretty good too. A network adapter of any kind provides great connectivity options.

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The 100% Server Uptime Illusion

Posted on May 25th, 2010 by Victoria Pal in Tech

100% server uptimeYou've seen 98.9%, 99.9% and even 100% server uptime labels on hosting sites. The first thought which comes up to people is "Well, 99.9% sounds pretty well, 0.01% is no big deal" and they are right. The fact many people are missing is the fact that even if the server is reachable, it doesn't necessarily mean it's fully functional. So many other things can go wrong with a server. A 99.9% uptime sticker is no guarantee that your business won't face other problems, while the server is up and running. Hosting providers calculate uptime in ways that aren’t intuitive from a user’s perspective, not taking in account certain website downtime.

  • First of all, not all downtime is counted. Scheduled maintenance is not part of the equation. Several hours of downtime is not what hosting companies would include. When monthly server uptime is calculated, such planned service interruptions are not included (deducted).
  • Some, if not most, hosting providers tend to overlook shorter downtime periods. 3-5 minutes of unavailability are not considered significant and don't end up on the 99.9% sticker. You can see how multiple short downtime periods can make a difference at the end of the day.
  • 0.01% means twice the trouble. 99.9% uptime means 8 hours and 45 minutes downtime per year. So when you go down a notch to 98.9%, your calculated downtime goes up twice to 17 hours and 30 minutes.
  • Resources are limited. "Unlimited" is just a nice way to sugarcoat "enough for the majority of common users". Your business might not be a common one and demand might be high. There might be other significant sites, sharing the same hosting hardware. At one point it can all build up to an overload, resulting in poor loading times, broken transactions, even website. The server will still be online, but the performance won't meet your needs. Application monitoring is a good way to find out such problems quick and easy.

100% uptime is not feasible. Eventually something will go wrong. Network backbones will cause problems, power failures will happen, server software and hardware will fail every now and then and human error will always be a considerable factor. So, my advice is: Don't try to find the ultimate provider, as it doesn't exist. Instead find a decent provider with good server uptime and performance, 24 hour technical support and frequent backups. Oh, and why don't you go for a nice remote website monitoring service, just in case. It might be the best money you have ever spent.

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Google Servers - The Old, The Small and The Container

Posted on May 20th, 2010 by Victoria Pal in Tech

Server

Servers come in different shapes and sizes. They serve different purposes. Sometimes they are dedicated and sometimes they fulfill various tasks. A common impression of a server looks pretty much like the image on the left - hard drivers, a lot of circuit boards, numerous cables and a huge server rack to house it all. Curiously, this is Google's first production server (about 10 years old). This server, along with about 30 others, is what allowed the company to grow big at a minimal cost.

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Status Code 404 - Not Found

Posted on May 19th, 2010 by Victoria Pal in Monitoring

404 error page not foundIt is quite common to see "404 Not Found" page instead of the requested one. This is a standard status code, informing the client that the server has not found anything matching this precise URI (short for Uniform Resource Locator). In other words, that is what you get when the server is not able to find the page you are trying to load, due to one reason or another.

This status code is commonly used. However, it is not the only error code you might get. 404, along with other 4xx status codes, is a client-side error, meaning that the user either misspelled or requested a page that is no longer there. On a different note, status 200 is the most common server reply you get. You don't see it because the request succeeded to display the requested resource.

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It Don't Mean a Thing If It Ain't Got That Ping

Posted on May 18th, 2010 by Victoria Pal in Tech

PingPing is one of the most well known and easy to use computer network tools. Its basic application is to test the availability of hosts across an IP network. The ping tool was written by Mike Muuss way back in December, 1983. Its practical use and reliability was undeniable until 2003 when a lot of internet service providers began filtering ICMP ping requests, due to growing thread from internet worms and basic DDoS attacks. Nearly 3 decades later, ping stands tall providing common computer users, webmasters and network administrators with valuable information.

Check your network adapter

Common users can use ping from their local machine to check if their LAN, WLAN card is enabled and working, by simply pinging itself. The command will look something very similar to this:

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