tirsdag den 20. oktober 2009

How does it fail: Usb stick

Small, cheap, easy to use and they can take much more of a beating than a harddrive. Their small size is their worst enemy: Forget it in your pocket when washing, sit on it, drop it into the toilet or just plain loose it. Simple stuff no technology can solve.

These small miracles are not everlasting. All flash circuits have a limited number of times you can write to them. The cheap ones the count is 100.000 times, the expensive ones it is 1.000.000 or a bit more. You might not use a flash drive so many times, but if you use it as a working drive, and a program saves changes to it a lot of times, it might eventually kill the drive.

onsdag den 14. oktober 2009

Everything can fail

The most basic principle in making a good backup strategy is: Everything can fail.

Harddrives break down, DVDs are suddenly unreadable and the fancy "in the cloud" online backup company goes out of buisness.

Think this way: At any time there is a probabillity that a given data storage will fail you. When that happens it will take some time before you realise it, it will take some time to get a replacement storage and it will take some time to make a new backup.

lørdag den 3. oktober 2009

Making your own backup strategy

Having read the previous posts, you know that one backup might not be enough. There are many ways to make backup and if you want to be well protected without paying too much, you must make a backup strategy for your situation.

In order to make a backup strategy you must know about different backup technologies, their price, ease of use and how they fails.

Then you must weight the pros and cons of each technology and make sure that the advantages of one technology will cover for the disadvantages of another. One technology might be fast and easy to use, but will not protect against a major disaster. That can be combined with one that takes more of your time, but can be applies less often, because a major disaster does not happen a lot.

Some of the upcoming posting will talk about such technologies, pros and cons.

torsdag den 24. september 2009

Why 3 backups? - Risk analysis

Some times you will hear that people make more than one backup copy why?

This is based on this simple risk analysis: At any time there is a certain risk that any copy will fail. If you have 2 copies and one fails, then you only have 1. If that fails before you can make a new 2nd copy, you will loose all of your data.

If your are on holiday or it is your backup that fails it can take quite a while before you notice it, and thus the other copy have much more time to fail. The longer time something has to fail in, the higher is the risk that it will fail.

A 3rd at another location will also protect against theft, fire, flooding and other major events.

torsdag den 17. september 2009

Cheap and safe.

No matter how you backup your data there is always the risk that the backup fails. In the time, from either your main copy or your backup has failed, only one copy of your data exists. If the other copy also is lost you have lost your data dispite of backup.

For this reason many copies of your most important data might be worth while.

Burnable DVDs are good for this, because they are cheap and can only be written once anyway. Select your most important data, so you can pretty much fill one or maby more DVDs.

One way of storing these DVDs are to put the newsest in a place outside of your house where you come often. That might be at work or at a friends house. When you visit some far away friends or family, bring one of the older DVDs and have it stored there.

Then, in the worst case you might not have all of the newest data, but you have most of your important data. And it is done for very little money.

torsdag den 10. september 2009

Simple backup for everybody

Here is a way of doing backup which will work well for most people:

Buy a USB flash drive and copy your data to that about once every month.

For some documents and pictures a 4 or 8 GB drive should do it. If you also want to backup some movies you should go for a USB harddrive.

Price

Very cheap.

Ease of use

Easy but requires some manual work. You don't have to set up any accounts, automatic schedules or technical stuff. Instead you have to do the work yourself and some people don't want to bother doing that.

You might want to use an online solution - wait for another posting about that.

Safety

Better than nothing. This solution will protect you against a crashed harddrive and damaged or deleted files. If you store the drive in another house (e.g. at a friends place) you will also be protected against theft, fire and other kinds of local natural disasters. Big scale disasters such as earth quake or massive fires requires that the drive is much further away. Consider an online solution or a "NAS friendship" - see upcomming posts for that.

torsdag den 3. september 2009

What, why, how?

What is backup?

Backup is making additional copies of data, in the case the original copy becomes inaccessible. In other words: Make a safety copy of your documents and pictures, so they will not disappear when your computer crashes.

Why

There are two kinds of people in the world: Those who have lost data and those who will loose data. You better have another copy when you loose yours.

Usually it is harddrives that break, but it can also happen due to computer virus, errors in programs, theft, water damage, fire, natural disasters and in many other ways.

How

Just make another copy of the data. That's it!

Well, depending on how you do that, you will get a cheap or expensive solution, which might be easy or hard to use and which may protect you just a little or very well. This blog is basically about those 3 paramters: Price, ease of use and protection.