maintaining computer

Saturday, January 23, 2010

Data backup strategy

Although computers are now used by almost anyone and is used to store a variety of important data, but I see there are very many people who forget to take into account
the possibility of data disappearance tsb. Computers remained a complex electronic devices no matter how Microsoft Windows made simple visible / not complicated; and occurs many opportunities for things not on your data terdua very large - viruses, hard disk damage, damage to data files; all of which can occur in many ways.

For that is the important thing for you to create a data backup strategy, to prevent loss of data from the computer. I will be listing the various things you can do the following with different strengths and weaknesses.

1. Diskette

This general is a bad idea. Floppy disk is a medium which is not reliable, so many things that can break it - scratched a little, get a magnet, got hot, folded / terduduki / crushed, head drive yg no longer accurate - and you even set aside only your data is corrupted (due to mold) . ALWAYS AVOID STORE IN YOUR IMPORTANT DATA disks.

2. Another hard disk.

If you have more than one hard disk, this is the way of data backup most feasible; faster and cheaper (no need to purchase additional equipment). Collect your important data in a directory on your hard disk first, and are routinely duplicated the directory to the second disk.

The downside, your data is still collected on the same computer, so problems such as surge / spike (surge current) is likely to damage the hard disk simultaneously.

3. CD-R (Recordable CD).

With the proliferation of CD-R drive so even if you do not have it but you probably have friends who have. Take advantage to backup your data, because such strengths cheap prices (CD-R blank if not wrong the price is

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under USD $ 10-thousand now), very reliable (data on CD-Rs can last for decades if stored according to recommendations of its manufacturer), and its capacity is large enough if only to simply save the file Microsoft Word (640 MB) . One more thing is that you can access your data2 simply inserting the CD into the CD drive tsb on any computer is very easy to return access your data. The drawback is the speed of backups is a bit slow (640 MB will usually take about 1 hour), a limited capacity to backup large amounts of data (not feasible to backup data in gigabytes), are easily damaged (dropped to the floor, or let the kids You bermainmain with the CD - good-bye data), and drives an expensive price (even though it is far cheaper when compared to some years ago).

4. Zip drive.


Pros: Pretty fast for data backup, drive prices quite cheap now. Disadvantages: 100 MB is sometimes not enough to save all your data, Zip disk can not be guaranteed reliability, ratio disk price / capacity is too expensive, the technology was already obsolete.

5. Jaz drives.


Pros: Pretty fast to backup the data, large capacity (2 GB).
Disadvantages: Price disks are still expensive - the ratio of the disk price / capacity lost from the hard disk (!), Maish long-term reliability is questionable.

6. QIC tape drives.


Pros: The price is cheaper than the drive DLT drives, cartridge prices are much cheaper, can be
data via the parallel port only

Disadvantages: not for DLT Capacity (maximum at the time of this writing is 30 GB),
backup speed is very slow, sometimes not reliable (!).

7. DLT tape drives.


Pros: Very fast in data backup, huge capacity, reliable. Disadvantages: Price VERY expensive (usually around a thousand U.S. dollars).

8. Internet.


This new alternative that may be quite feasible, thanks to the emergence of various websites that provide data storage services free of charge on the Internet. Some examples, Briefcase (http://briefcase.yahoo.com - 25 MB), Freediskspace (http://www.freediskspace.com - max. 300 MB), X-Drive (http://www.xdrive.com - about 50 MB), and others.

; Free, and backup your data can be accessed from around the world. Disadvantages: not efficient for large amounts of data, especially when your Internet connection via a modem.

Also very important not to ONLY backup the data on the Internet, because this is a free service that if suddenly (for example) they are having problems then nothing that you can also lakukan.Backup your data with other alternatives.

One thing that is important for you to remember always:

There is no "too many backup" for your data

Always duplicate your important data as many

Personal experience, I made a few copies of my important data2. My first copy it to my hard disk is one more. My second copy it to your hard disk in the computer my brother. My third copy it to CD, and stored at home. My fourth copy it to CD and I take if

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travel far, so in theory even if the worst happens (such as burning houses, etc.) I still data2 important will be safe.

You would think, "Boy trouble at all". But what happened? My hard disk crash, so the data is lost. Then the data in other hard disk is also lost / corrupted. And, backup data on the CD in my house could not be found ... .

still no backups of data on the CD that I carry, and finally the important data collected over the years come back safely. I can not imagine what it would be if I did not do the data backup processes such as these 4 layers. After that I was getting to intensify and oversee my data backups are more stringent.

This is just for personal data, to company data should be more comprehensive, longer procedure. But still, too often I hear how the company refused to backup their data because "they're expensive tape drive", etc.. Same name for this problem.

Some TIPS:

  Collect important data you have in one directory; example: C: MyDocument. Disciplines such as this would be easier for you to do backups of data tsb.
(imagine for example your data is in C: /, D: / MyDocument,

C: / ProgramFiles / MicrosoftOffice / Word, and C: / ProgramFiles / MicrosoftOffice / Excel? You will first reluctant to trigger backup tsb data2)

Intervals   How good data backups?

Actually it depends on how often you update your data. If your data is mostly just arsip2 rare files are updated, then maybe one
once sufficient

But if every day there's always the addition / update data, then based on the experience
maximum of once every 3 days.

For companies; standard strategy is to use a backup system grandfatherfather-son, the fruit of tape 5 is used for data backup (incremental) each day, and 4 pieces of data backup tapes for each weekend (1 tape each week, so to cover the data for one months) for a full backup, then 1 piece of tape for a full backup monthly.

 Test your data backups!


There is no point you have dozens of backup data if it can not be accessed anyway? But in reality there are many people who only backup their data without
test whether these data it can be accessed again.

This point was particularly relevant to the QIC tape drive, I personally have experienced myself how corporate data over the years that every day turned out to be a backup when needed could not be restored, really scary. (although in the end can also be accessed by using the other tape drives, but maybe I'm just lucky it).

2. Anticipation Computer Virus

Did you know that a proper antivirus program can protect your data can also be dangerous if not used correctly?. Why? What can we do as a user?, What should we do as a programmer antivirus?.

Since first discovered the virus has undergone technological developments large enough, so that there Antivirus program. Unfortunately development Antivirus usually only pursue the development of the virus and not to precede it. Antivirus is missing (the technology) can actually invite danger to the user.

When the viruses successfully detected its presence, that viruses are always emerging with a new more advanced technology that makes antivirus become helpless. Old antivirus for example, always be on-'tipu 'with stealth technology, so when this antivirus

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trying to detect files that other stealth viruses had just spread himself into every
files examined.

In various magazines of course you've seen any antivirus programs "unit" (specific) which aim to detect one type of virus. Antivirus products usually do not make the ways the right to use this antivirus program, although specific antiviral great risk if not used correctly.

Specific antivirus can detect only one type of virus (and perhaps some of its variants) and is usually able to disable the virus in memory. If you find a virus and you are sure the virus name you can use these Antivirus, but if you do not know, you should not try. If you find that active virus is another virus, which certainly was not this detected by antivirus, the antivirus is a virus it can spread throughout the existing program files examined.

A more sinister danger is if the antivirus detect a virus one and one to clean so that the program file you're trying to fix it become damaged. This incident never happened for example in the case of DenHard virus, the virus is really similar to die hard, but this virus uses different techniques to restore the original header file, some antivirus just trying to clean up corrupted files where the virus program is. In addition to the cases of the virus occurred DenHard, the program cases ever (and probably still will continue to) occur in some viruses. One reason for the virus makers make a similar virus is so difficult to clean the virus, because the antivirus makers do not like it if the virus can easily be cleaned by the user.

HAZARD SOURCE ANTIVIRUS PROGRAM

Antivirus programs can be dangerous for the following reasons:

 Some antivirus programs using only simple techniques that can be easily
deceived by virus makers, for example antivirus program to check only a few bytes at the beginning of the virus, the virus-makers could have made another version of the virus in the early part of the same but different in other parts of the important, such as in routine encryption / decryption original file header. This would make a destroyer antivirus program file rather than rescue the files. Some anti-virus also can be deceived by varying the antivirus signature files. Signature file is a file that contains the ID of all known viruses by antivirus, if the ID is in turn the antivirus would not know him. A good antivirus should be able to check if the file signature is changed.

 Antivirus program does not make backups of the file is cleared. Often the antivirus program
(especially specific) does not provide the means to create a clean backup files, and it is very important if the cleaning process failed.
 Antivirus program does not do self-check. Self check is necessary, the antivirus program can be
modified by someone else before it reached the hands of users. Antivirus programs are usually commercially using self checks to make sure he was not modified by anyone, but some are not and it is harmful. In antivirus programs locally, which often included several articles on the computer, typically includes the source code, you should compile the source yourself if you doubt the authenticity of his exe files.
Antivirus Program Resident  can easily turn off a good Antivirus resident should
can not be detected and uninstalled easily. Examples of resident antivirus is less well VSAFE (in DOS package). VSAFE can be detected and disabled by using interrupt (you try to learn / debug vsafe program in DOS so you understand).
Users will get a false sense of security by using this kind of antivirus. There is no sense of security it is better than a false sense of security.

 antivirus program does not give warning expired. Over time,
viruses that appear more and more and more sophisticated technique. A good antivirus program should give a warning if used Antivirus'm too out of date. This is important so that antiviral incident does not happen again spreading the virus.

HERE'S WHAT YOU NEED TO DO AS A USER

As a user antivirus program there are several things you can do to minimize the risk of the use of antiviral

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1. look for a good antivirus, both here means the program can be trusted to
detect and eradicate the virus. Do not be lulled by the promises offered by the antivirus vendor, and do not be swayed by brand names are also quite popular. Try to find a comparison between the various anti-virus in various magazines / sites on the Internet.

2. always use the latest Antivirus, you can get it from the Internet or from some
magazine. Antivirus old has a big risk if used (more than 6 months have been very dangerous).

. create a backup for your data and programs are important. 4. virus cleaning process done correctly if you find the virus 5. Antivirus programs ensure that you get is the original, chances are someone has
antivirus such change, or perhaps menularinya with a virus. 6. Call an expert if you feel you can not overcome the virus on your computer or network.

Step a good cleaning process is as follows:

If you run a personal computer

1. Boot your computer with a clean startup disk from the virus (and the write protect) 2. Run the program virus scanner / cleaner at a 3-infected file. Try running the file, if the file becomes corrupted, do not go anymore 4. If the program can run smoothly, cobakan once again on some files (look for the size
small, medium and large). The larger size files need to be checked, this file usually contains internal overlay that makes the file damaged if exposed to the virus.

If you are a network administrator, you should take a sample of the virus to the disk and tried to clean it on another computer, this is not to interfere with the work may be done by someone else. It is also to anticipate, the possibility of new viruses that are similar to other viruses (imagine what would happen if there is any cleaning so the entire program on a network can not be used!). If you fail to be cleaned need to call an expert to deal with, or seek further information on the Internet. Experiments on some files aim to prevent any false detection and / or repaired by antivirus programs. If the virus is considered dangerous and network activity can be delayed temporarily, may temporarily shut down the network.

THIS PROGRAMMER AS YOU NEED TO DO

We have to be a good anti-virus programmer is not easy, you need to know programming teknikteknik viruses every day growing more difficult. Antivirus program that you create should also follow the development of virus technology. To make a good antivirus program is not easy, but there are some things you need to remember as the creator Antivirus if you want to program you used someone else, and do not endanger the person

1. Your program should be able to turn off the virus in memory, and can give a warning if
there is something strange on the user's computer memory (eg a large base to less than 640 Kb)

. In making the virus ID choose several locations, both locations are at the beginning of the virus and the
an important part of the virus (eg decrypt the header in the original program) is to make sure no one changed the location and encryption system (if any) the original program header.
3. If the data / header in enkrip, verify the data obtained from the calculation, for example, see
whether the CS and the original IP to the calculation is still in the file size limit, or whether the first JMP instruction at reasonable COM files (less than a length file).

4. Create a backup file if the file is cleared feared damaged

. Perform a self check at the beginning of the program. If not all parts of the program could be in a self check, the
ID the virus needs to be checked whether the change or not (eg checksum). 6. Make a clear explanation of how the use of antiviral

7. If the program can only run in DOS always check when the program starts if
the program is actually running in DOS

8. If you want to make the resident antivirus program, do not wear ID viruses which are not encrypted in
memory, other antivirus antivirus did not know you are, it will assume the existence of a (or several) active virus in memory. This can happen, because some anti-virus check all the memory of the ID virus.

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9. For the non-resident antivirus technique No. 8 also needs to be used, it is necessary for the program
other antivirus programs do not think this virus. Sometimes the programs also left a scar on the memory, which may be suspected by the other antivirus as a virus. If you do not want to apply these techniques, you can delete the virus ID variable memory after use.

10. If possible, for polymorphic viruses using heuristic methods (and / or emulation) for
scan and emulation techniques to decrypt, or restore the original program.

10 it should be enough, you can add it yourself if necessary. For example the problem of scanning speed and others.

TIPS

  Update anti-virus Anti-virus MUST be updated regularly, so that can always ward off viruses
new and continued to appear every day. Visit the site regularly used by antivirus products.

  It is also to stop using Microsoft Outlook, then you will be safe from
various viruses. Use other software such as Eudora (http://www.eudora.com) or Pegasus Mail (http://www.pmail.com)


free and good enough to include Grisoft (http://www.avast.com). Antivirus which is basically the same relative, the important you do regularly updated as described above. In addition to commercially available anti-virus anti-virus
(http://www.grisoft.com) and Avast!

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  Physically clean the computer both the exterior and in the case of dust and
foreign objects other, which can affect the performance and functions of computer equipment.

  Ensure the cooling system and air circulation in the well casing
so that the temperature can be maintained computer. For computers that operate 24 hours
nonstop placed in the room suggested that use cooling (AC)

  Defrag should not be too frequent. Defrag is usually only done if the process
read-write to the hard drive was slow, will install a large program, or would mengkopikan large files to the hard drive.

Hard disks are now very fast, so the data is fragmented, usually not much to slow. The slow computer is often caused by something else; lack of memory, no viruses, and so on. Besides full defrag very intensive, so if done too often will shorten the age of the hard disk.

3. Your PC safe?

Do you have a lot of important data stored on your computer at home?, You are often annoyed with people who always disrupt the work, or you're often surprised with your data that is often missing. If your answer is yes, you need to read this article.

Maybe you've had your important data you store on your computer in the house suddenly disappeared or changed here and there. Sometimes you do not know who did it and sometimes you know that the culprit was a rookie who did not intentionally damage your data. Although you know the perpetrator and had advised him not guarantee that such things will not happen for the second time so you need to protect your computer. Actually there are enough articles that discuss computer security but I will try to discuss this in more detail along with the weaknesses of each way there and how overcoming it.

Who's Who Need in Beware

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Before performing the steps of the previous security we must know who the enemy we are in a secure computer. Which became the main opponent of the security of our computers are our own, our carelessness more often cause damage than others. Omission to scan new programs for example, can destroy all the data you have. Because of us is an enemy there is no other way than to apply the discipline to yourself.

The second enemy is near you, has been proven through research that the perpetrators of computer crimes are those near the victim, or in companies that the perpetrators are those who actually trusted to safeguard the company. It's also possible that your neighbor does not mean to spoil your data or see your data but they can still do it by accident. Another enemy is the stranger, this is the maker of their viruses, trojan horses, time bombs and others who use it only to destroy others without a clear purpose.

Physical Security

This is the first security level and the most secure, put your PC in a safe place. Lock the door when you leave. Maybe this is the most secure, but maybe there is a thief who steal your computer. If your data is important and that the computer is
only will you use this is probably the most simple and most secure. However, it should be recognized that not all people have computers really for personal use or to have a private room to put it down.

BIOS password, the first defense

In terms of computers is your first defense. If you turn on your BIOS password facility, then the computer turned on so you'll be presented with a view to asking your password. Some people use this facility and see it as a safe way.
But there is also refusing to wear, the reason is usually because it looks less cool. Usually the use of passwords can be arranged, can be used for securing the whole system or BIOS setup security enough. First I will discuss the weaknesses when you use security for the entire system.

Actually, the BIOS password has significant weaknesses. On output AWARD BIOS version 2.xx, 4.xxg version and version 5.xx or above have the password, called the default password.
With this default password that everyone can break into without the original password. Initially the default password is only used by the technicians if you're trapped AWARD but apparently this has been used incorrectly by many people. For versions 2.xx and 4.xxg same default password for each computer (might be an article about this I will put on the homepage of this, if I've got time). For the version 5.xx or above the default password for each computer in the case of two characters behind him so that a total of 676 default password (for the last two characters only ranged from 'A' .. 'Z'). I myself still have not examined whether the two characters behind it depends on the BIOS serial number.

BIOS made by other manufacturers do not have weaknesses that are owned by AWARD, but you do not get too excited, there are other ways to bypass BIOS passwords. You need to know that the BIOS password is stored in a CMOS chip with the BIOS setup data, these chips get power from the CMOS battery so that the data stored in it remains secure even if the computer is turned off. Exceptions occur if the CMOS battery is running low or short circuit occurs. Well the last exception that is the problem, if there are people who open the case and connect the tip of your positive and negative end of the CMOS battery, all existing data in the CMOS will be lost including the BIOS password. If this data is lost people could freely enter.

Security to the problem is to put your system unit in a difficult place issued, or add the key to difficult to open. For the default password problem AWARD, you can update your BIOS or change the default password with a program from AWARD. But do not worry too much, not many people know this default password problem.

You can also create a security setup at all, it is useful to avoid an inexperienced orangorang changing the contents of the setup. The weakness of this technique is the password

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can be removed from the operating system. I know of no way to prevent a password to delete this program from the operating system. Many programs can be used to remove this password, even with BASIC or DEBUG can. The program is widely used to remove the password is usually the contents of CMOS timers programs (eg, from Norton Utilities), by entering data from the system CMOS berpassword not, then the password will be deleted.

Operating system level security

For you DOS users may be familiar with security by creating password in autoexec.bat. You need to know that the DOS versions of the latest (if not mistaken from version 5) can be inhibited autoexec.bat trip by pressing F5 or F8 (on MS-DOS), the purpose of this facility is to trace the course of the startup files but turns out this has been given a new problem. Another way is to put a password on boot program record or disk partition. Both ways are very insecure, because everybody could have the computer boot from a DOS diskette carried.

For the Windows operating system 3.1 or 3.11, both have a very big weakness. Because they stand on DOS, then all operations can be managed from DOS, for example, we create a password by putting the name of the program in RUN line in WIN.INI file, the file can be modified from DOS. Not much we can do with this weakness.

Windows 95 and Windows 98 also has the same weakness, although there are some people who claim to be able to protect Windows 95/98 with a password but I've never tried it, because I lack Percy with these programs. You need to know there are so many security lubing in Windows 95/98. You can press F8 at the beginning of the process that lets you boot into DOS and modify all Windows system files such as WIN.INI and registry files. You need to know also that in Windows 95/98
programs can be executed by writing his name in the RUN line in the WIN.INI file, by putting them in the StartUp group or it could be by putting them in key RUN, RUNONCE, RUNSERVICES or in RUNSERVICES ONCE in branch HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion at registry in this way that programs always appear in the startup in run (In addition to using both of the above). Maybe you think the registry is not
can be modified from DOS, you are wrong, the program regedit.exe in Windows 95/98 startup disk can change the registry file into plain text files and vice versa so you can change it, including removing the program line that password.

Emphasis F8 (And the other buttons) on Windows 95/98 could be turned off by putting a line BOOTKEYS = 0 in MSDOS.SYS file. As I've mentioned the way the program was still possible to enter using disknya own startup. You can just turn off the A drive that can not be used to boot, but you will be trouble if one day you experience problems Windows.

Linux is an operating system that is currently quite widely used and fairly safe, but for the laity operating system is still quite difficult to use. If not properly setting the system
This operation has several features that enable people default to break into.

For other operating systems I mentioned are not here because most PC users in Indonesia is still wearing the three operating systems on top. As you can see the level of security in this operating system very easily breached. Solutions that really good I think hard, every operating system has weaknesses. And any operating system will not be able to resist an attack if the attacker has physical access to a computer.

Application-level protection

If you have important programs that you want to protect you can give a password. Some programs are dangerous or confidential password system has been implemented as a part of it, such as NU, PCTools and others. There are many DOS programs that can give passwords to the files EXE or COM. Unfortunately not much can
provide the same thing for Windows EXE files. Oh yes, be careful with programs that provide a password on a DOS EXE file, first make a backup file because some files EXE files can be damaged if given a password. For the programmer assembly, unpacking such passwords is not difficult, because the way the program can be tracked by using the debugger.

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Document-level protection

This is the last level of protection, if it successfully dismantled the important data may be readable by others. For programs that provide the password when saving the file you can use this facility. But be careful a lot of programs that can unpack.