Backupabackup, or the process of backing up, refers to the copying and archiving of computerdataso it may be used torestorethe original after adata lossevent.Backups have two distinct purposes. The primary purpose is to recover data after its loss, be it by data deletion orcorruption. Data loss can be a common experience of computer users. A 2008 survey found that 66% of respondents had lost files on their home PC.[2]The secondary purpose of backups is to recover data from an earlier time, according to a user-defineddata retentionpolicy, typically configured within a backup application for how long copies of data are required.we must first understand the different types of backups that can be created. They are: Normal (Full) Backups Incremental Backups Differential Backups Mirror Backups1. Full BackupsA full backup stores a copy of all files and typically occurs automatically according to a pre-set schedule. Files are usually compressed to save space, however, even when compressed full backups may consume a lot of storage. Additionally, full backups cause heavy access to the backup disk, which shorten disk life and consume network bandwidth.The advantage of full backups is the ease of restoration. Restoring a file requires only the file name, location, and date from which to restore the data. Restoration is relatively straightforward as long as the backup files from that date or time are available.Although full backups are certainly comprehensive, they may be more robust than many businesses require. It is important to consider that only a small percentage of files change from one backup to another. Consequently, performing full backups will yield multiple identical copies of files andconsume valuable storage space on the backup medium.2. Incremental BackupsIncremental backups save space by backing up only the files that have been created or changed since the last backup. The advantage of incremental backups is that the volume of data backed up at each iteration is much smaller, which in turn saves space on the backup medium and uses less network bandwidth.However, incremental backups increase computing overhead, because each source file must be compared with the last full backup as well as the incremental iterations to determine whether data is new or changed. Additionally, it is more complex to locate a specific file to restore as it may require searching several iterations. To completely restore all files requires merging all iterations while taking care to keep only the most recent version of each file.Many enterprise backup strategies include a combination of full backups and incremental backups. For example, running a full backup once per weekon weekends when network and computing resource demands are lowerand scheduling incremental backups on weekdays. Backing up files with this combination enables a restoration that does not require looking through or merging more than a weeks worth of iterations.Some strategieslimit the impact on disk backup storageby copying older full backups from disk to tapes, which are then stored off-site. Although this approach is more secure than storing both the file system and backup media at the same location, the manual work to change tapes, label them and transport them is time-consuming. Additionally, it creates a difference between the finished backups that are stored off-site and the current state of the live file system. In the event of a disaster, any data changes that occurred since copying the last full backup to tape may be lost.3. Differential BackupsDifferential backups are similar to incremental backups, except that each backup operation stores the new and updated files since the last full backup. For example, if a full backup was performed on Sunday and a file changed on Monday, that file will be part of every differential backup until the next full backup is run.Using differential backups simplifies recovery because only the last full backup and the last differential backup is needed to create a complete restoration. As with incremental backups, differential backups need to compare current and already-backed-up files to identify any changes. However, differential backups require more space and network bandwidth compared with incremental backups.4. Virtual Full BackupsVirtual full backups use a database totrack and manage backed-up data, which helps avoid some of the pitfalls of other backup methods. A full copy, or replica, is taken only once and does not need to be taken again as long as the storage mediumtypically a network-attached storage locationremains unchanged. The virtual full backup periodically synchronizes backup data to the database.Virtual full backups are generally performed automatically by backup software. The user experience appears the same as that of a full backup. Restoring one file or an entire disk is a matter of choosing a preferred recovery point and the file or files to recover.Mirror BackupsMirrorbackup includes all files that have changed since the last normal (full) or mirror backup, missing files are also be deleted from the backup set. The resulting backup archive consists of either one compressed file or one folder.

Backup tools :Cobian Backup:Cobian Backupis free backup software that supports scheduled local and remote backups. Users love its rich feature set, as Cobian supports nearly every feature of its shareware alternatives. All current versions of Cobian are freeware, but the latest (version 9) is no longer open source.SyncBack:SyncBackis full-featured backup software available in both freeware and shareware versions. The freeware SyncBack has a few limitations that the shareware version doesn't, like inability to backup open files, but both versions offer extensive featuresincluding backup profiles and options for local and remote backups. The shareware version of SyncBack will set you back $30.Acronis True Image:Acronis True Imagecreates full live disk images of your PC so that when the time comes that you need to restore a backup, you're not just restoring filesyou're restoring an exact copy of your PC as it was. The latest version of Acronis supports excluding individual files and folders from your image or you can set criteria for the data that you want to back up (in case you don't actually want to include everything in your disk image). Acronis True Image costs $50 and a 15 day trial version is available.Carbonite:Carboniteis an online backup solution similar to MozyHome. For $50 a year, Carbonite provides unlimited online backup and is another set-it-and-forget-it solution which offers off-site backup to remote servers. The biggest difference between Carbonite and Mozy is the price: Carbonite is $50 per year upfront compared to MozyHome's $5 per month, which adds up to $60 a year but doesn't lock you into a year. Carbonite does not offer a free version like MozyHome Free's 2GBs, but there is a 15-day trial. For more user comparisons, check out ourCarbonite vs. Mozy faceoff.1. AOMEI BackupperIf you like your backup programs to be simple thanAOMEI Backupper's straightforward interface will appeal immediately. Choose the drive or partition to back up, the destination drive, and a click later Backupper will be creating an image for you.2. EaseUS Todo Backup FreeJust like most free (for personal use) editions of commercial products,EaseUS Todo Backup Freehas a few limitations - but the package still has more than enough features for most people.The program can run both image and file-based backups, for instance, manually or on a schedule. You're able to run full or incremental backups.An option to limit write speed reduces the impact backups have on your system performance. It's possible to individual files or folders, or an entire image via the program's recovery disc. And there are tools to clone and wipe drives, too.On the negative side, you don't get encryption, there's no differential backup, and you only get a Linux-based disc (not Windows PE). But EaseUS Todo Backup Free still looks like a great program to us.3. Redo Backup and RecoveryRedo Backup and Recoveryis an imaging backup tool with a difference. Instead of installing a program, you download a large (249MB) ISO file, and burn it to CD or USB key drive. Then just boot from it to launch a simple tool which can back up your drives, and restore them later (even if Windows won't start).There's also an undelete tool, and even a web browser if you need to look for help on your PC problems.The program isn't exactly convenient, then. You can't schedule backups, they all have to be run manually, and there are very few options.But it's also easy to use and free for everyone, so if you only want to run backups occasionally - or want a system you can use on any PC, without installing software - then it might be worth a look.5. Macrium Reflect FreeOne of the most popular free (for home use) disk imaging programs around,Macrium Reflect Freedelivers a solid, if basic feature set via an easy-to-use interface.The program doesn't have incremental or differential backups. And you don't get encryption or password protection. This does make creating a backup job very easy, though (choose the source drive, the destination, maybe set the compression level and you're done).7. FBackupFBackupis a capable file backup tool, free for both personal and commercial use. The interface is simple and straightforward, and there are a number of features you don't always see elsewhere.Plug-ins allow you to back up individual programs with a click; there's support for include and exclude filters; and you can run "mirror" backups, which just copy everything without zipping it up (which makes restoring files very easy).

Backup Methods[edit]Backups are the vital storage of data, so if data is lost there is still an identical copy that will allow the key data and information to still be accessible and used for day-to-day work flow.[14]Backups can also be done through online storage[15]and can allow continuity of service, and also help to ensure that vital data is not lost in the event that the data storage fails. This is particularly useful for large organisations as data make up the vital pieces that will allow them to be able to carry out their work.These are the Backups most typically used in large high technology organisations:Normal (Full) BackupsIncremental BackupsDifferential BackupsMirror BackupsFull Backups[edit]Full backup is the starting point for backups and is generally the first backup that is made. It involves backing up all of the data in one go, and is a good method of backing up when there is not much needed to be backed up,however if there is a lot to be backed up then the back up may take a considerable amount of time.[16]Advantages[edit] File restoration is relatively easy and can be done from one backup. The files can be backed up on to one central storage unit instead of many.Disadvantages[edit] A full backup is more time consuming than other backup options. Full backups require more disk, tape, or network drive space.Incremental Backups[edit]Incremental backup refers to the type of backup that stores files since the last backup that was made. This will mean that incremental backups take the lease time to backup, however restoration may take some time in order to be able carry out the process. It is a wise choice for large organisations who have lots in order to backup and as a result it will save time and can allow regular work flow rather than having to wait for backups to be carried out. However the restoration may take time as the last full backup and incremental backup needs to be restored in order for data to be brought back.Advantages[edit] Backup time is faster than full backups, as there is less needed to be backed up. This type of backup generally required less space then a full back up, and as a result more incremental backups can be carried out over time.Disadvantages[edit] Restoration time might take a considerably long times as all the other incremental back ups or a full back will need to be found. This may take further time actually looking for the back ups which is not very good for large enterprise to which time is so valuable.Differential Backups[edit]A differential backup is the backup for all of the changed files since the last full back up, This way it is able to do a very quick back up in addition to saving a lot of memory space which will allow for many backups in the future. The reason why it is saving memory space is as a result of it not backing up all of the files however only the files that have been changed. The advantages and disadvantages of Differential Backups are stated below:Advantages[edit] Differential backups require even less disk, tape, or network drive space than incremental backups.[17] It is the quickest in backup out of Full and IncrementalDisadvantages[edit] Restoration of an individual make take time to locate and as a result having to go through both Incremental and full backups Restoration may take some time as a result of the potential in having to retrieve both full and incremental backups.Mirror Backups[edit]Mirrored backups will backup the files on to two hard drives in order to ensure that the data is safe and is on two physical devices in order to ensure extra security in addition to being able to ensure that the back ups are not lost over time. This is a common strategy used by e -commerce businesses in order to be able to have continuity in service as if their hard drives fail then the online site cannot function.It will back up onto two hard drives to avoid losing back ups[18]

Classifying server problemsServer problems can generally be broken down into a few categories:

Hardware problems Operating system configuration problems Application/services-related problems

Its important to determine which category your problem fits into; otherwise, you can waste hours of troubleshooting time searching for a needle in the wrong haystack. What seems like an OS problem (STOP errors or unexpected reboots) may actually be hardware problems caused by faulty memory or a dying power supply.

Ten troubleshooting tipsDepending on the source of your problem, getting your server back up and running may or may not be quick and simple. These ten troubleshooting tips will give you a starting point for tracking down the culprit responsible for your servers demise, and address several of the most common server problems.

1. Develop a standardized troubleshooting routineTo identify and correct server problems most efficiently, you should have a standardized troubleshooting procedure that you follow each time something goes wrong. Troubleshooting server problems is generally more complicated than troubleshooting problems with client machines, because the operating system itself is more complex and because of all the services that run on a server machine.

Use checklists and forms(see sample here)to guide the troubleshooting process. This will prevent you from leaving out essential steps or overlooking the obvious.

Download our TPG server troubleshooting checklistPlaster thischecklistall over your server room so your entire staff has a step-by-step process to guide them through the server troubleshooting process.

2. Start at the bottom: Troubleshooting physical layer problemsThe first step in troubleshooting server problems is to determine whether the physical layer is functioning properly. This includes the server computer hardware, any attached peripherals, and the cabling. Switching out network cards or cables will help you identify whether the hardware is at fault. For testing long runs of cable that cant be easily switched, use a cable tester or multimeter.

If you have recently added new hardware to the server, make sure that its compatible with the operating system.

TipIf youre running a Microsoft server operating system, check the hardware compatibility list on theMicrosoft Web site.

You should also make sure that you have the correct drivers installed for your new hardware. Check the hardware vendors Web site for updated drivers.

3. Traffic control: Troubleshooting addressing and routing problemsOnce youve eliminated hardware as a suspect, you should check the operating system configuration. The typical business network runs on TCP/IP, and incorrect TCP/IP settings can result in addressing and routing problems.

Make sure the servers TCP/IP settings are correct. TCP/IP settings have been known to mysteriously change, for example, when you install an application. The most common situation is that the servers TCP/IP configuration is reset to make the computer a DHCP client. In most cases, servers should have static IP addresses. You may not notice the problem with a file or print server, but if your DNS server or domain controllers configuration is changed, your clients will experience problems.

Figure Aillustrates the TCP/IP settings on a Windows .NET server.

Figure A

Make sure that all TCP/IP settings on the server are correct when you have a network connectivity problem.

4. Identification required: Troubleshooting name resolution problemsWhats in a name? A great deal, when computers communicate using names, which must be resolved to IP addresses. If you have an apparent connectivity problem, always try pinging another system by both nameandIP address. If your server is out of touch when attempting to communicate by host name but is able to connect to other computers by IP address, check its DNS settings, WINS settings, and/or HOSTS and LMHOSTS files.

5. Trouble at the top: Troubleshooting application problemsThe applications that get installed on servers are different from the productivity applications that are typically installed on workstations. Server applications tend to be those that allow you to manage, maintain, or monitor the server (such as disk utilities, network monitoring, or sniffer programs, etc.), or those that add another server service, such as proxy server software installed on top of the server operating system.

Compatibility with the underlying operating system is essential. Programs such as Microsofts Certified for Windows 2000 program give you a way to evaluate the compatibility of server applications.

On a Windows server, check the application log (Start | Programs | Administrative Tools | Event Viewer) for application-related errors.

TipThe event logs are always a good place to start in troubleshooting server problems. In addition to the application logs, Windows NT/2000/.NET servers provide the system and security logs and additional logs (such as DNS and Directory Services) when specific server services are installed. The Error, Warning, and Information messages in the logs can be your best clues in determining what went wrong.

6. Paper chase: Troubleshooting print server problemsThe source of printing problems can be at any one of the following levels:

The printing device attached to the print server computer The configuration of the print server The physical connections between printer and server or server and network The configuration of the client

Your first step in troubleshooting print server problems is to make sure that the printing device is working and all connections are secure. Make sure the correct printer drivers are installed. Check that the print spooler service is running and to see that theres plenty of disk space on the server for spooling. Check the permissions set on the printer. If your network is a Windows 2000 or .NET domain, check group policy settings for printers.

7. Its in the mail: Troubleshooting e-mail server problemsE-mail is the most used network application today. Problems with the mail server can be due to the same connectivity problems Ive already discussed (hardware problems, TCP/IP settings). In addition, check the following:

Make sure that the Mail Exchange (MX) resource records in your DNS entries are correct. For more information about MX records, seethis fine site. Make sure the mail server has plenty of disk space for user mailboxes. You may need to impose limits on mailbox sizes if you have many high-volume users. If you want your mail server to receive mail from other mail servers, make sure that your mail server is configured to enable relay; otherwise, these requests will be blocked.

TipBe aware that opening your server to relays can make your server vulnerable to be used to relay spam through your server. Make sure the server is configured to accept relay messages only to your own mail domains.

8. Terminal condition: Troubleshooting Terminal Services problemsThe thin client solution is becoming more and more popular now that Microsoft includes Terminal Services built into its Windows 2000 and .NET server operating systems. For problems with your terminal server, check the following:

In a Windows 2000/.NET domain, check group policy and individual users account properties in Active Directory if users are unable to connect to the terminal server or are unexpectedly disconnected. Check the Terminal Services configuration settings (Start | Programs | Administrative Tools | Terminal Services Configuration). Make sure that the terminal server is running in Application mode; otherwise, only administrators can connect, and you can only have two active sessions at a time. Make sure that you have set up a Terminal Services license server and that you have sufficient licenses.

Figure Bshows the Windows 2000 Terminal Services Configuration tool.

Figure B

Make sure the terminal server configuration is set to the proper mode.

9. Cant call home: Troubleshooting dial-up/remote access server problemsA remote access server allows clients to dial in to connect to your network or establish a connection through a VPN over the Internet. If clients are unable to connect to your remote access server, check the general connectivity issues mentioned earlier, then check the following:

Make sure that remote access services are installed and configured on your server. Make sure the service is started. Make sure that your dial-in, PPTP, and/or L2TP ports are enabled to accept inbound remote access calls. Make sure that the remote access server is configured to allow connections on the protocol(s) that are being used by the remote clients (IP, IPX, AppleTalk, or NetBEUI).

TipTo view and configure properties of the Windows 2000 Remote Access Server, select Start | Programs | Administrative Tools | Routing And Remote Access, right-click the server name, and select Properties.

Figure Cshows you how to access the Remote Access Servers Properties.Figure C

On a Windows 2000/.NET server, open the Routing And Remote Access console and right-click the server name to view or configure its properties.

10. Listen for zebras: What else could the problem be?A good philosophy for troubleshooting server problems is the old adage: When you hear hoof beats, expect horses, not zebras. This means you should consider the more common sources of problems: hardware failure, misconfigured network settings, etc., rather than the exotic ones.

But what happens after youve checked out all the usual suspects and still cant connect to your server? Then you may want to consider some less commonly discussed possibilities:

Check your servers security settings, as well as any site- or domain-wide security policies that may be preventing connectivity. Check client licenses and licensing settings. If your server is configured to use per-seat licensing and is set for 100 licenses, the 101st client may not be able to connect even though youve purchased additional licenses, if you havent changed this setting. Always consider the possibility that the server itself is not at fault. Check the routers and the client computers to make sure that the real problem doesnt lie elsewhere.Preventative maintenance: The importance of backing upYou know how important it is to always have a current backup of your mission critical data, but do you actually practice what we all preach? Not only should you back up important data everyday, but you should also regularly do a test restoration to make sure that your backup software and hardware are in good working order. If not, you want to find outbeforeyou actually need it.

Power to the server: The importance of a good UPSPower surges or outages can be responsible for all manners of mysterious glitches, even if your server appears to have survived intact. Its crucial to protect your server with a good Uninterruptible Power Supply (UPS) to prevent this.

Good to go: Using VM software to mirror your server configurationThe ultimate in disaster protection is server clusteringcreating an exact duplicate of your server on a second machine, which can instantly take over the duties of your failed server so that your users experience little or no interruption in network services.

Clustering solutions range from expensive toveryexpensive. If your budget doesnt allow for this ideal solution, consider the poor mans version of clustering: Create a mirror of your server configuration on a virtual machine usingVMwareor similar software on another computer on your network. This virtual server might not stand up to long-term or heavy use, but it can take over your servers duties for a short time while you re-create your server, and it can be used as a guide in that re-creation process if you havent documented all of your servers settings as you should have.

Magnetic tapeMagnetic tape has long been the most commonly used medium for bulk data storage, backup, archiving, and interchange. Tape has typically had an order of magnitude better capacity/price ratio when compared to hard disk, but recently the ratios for tape and hard disk have become a lot closer.[6]There are many formats, many of which are proprietary or specific to certain markets like mainframes or a particular brand of personal computer. Tape is a sequential[clarification needed]access medium, so even though access times may be poor, the rate of continuously writing or reading data can actually be very fast. Some new tape drives are even faster than modern hard disks.Hard diskThe capacity/price ratio of hard disk has been rapidly improving for many years. This is making it more competitive with magnetic tape as a bulk storage medium. The main advantages of hard disk storage are low access times, availability, capacity and ease of use.[7]External disks can be connected via local interfaces likeSCSI,USB,FireWire, oreSATA, or via longer distance technologies likeEthernet,iSCSI, orFibre Channel. Some disk-based backup systems, such as Virtual Tape Libraries, supportdata deduplicationwhich can dramatically reduce the amount of disk storage capacity consumed by daily and weekly backup data. The main disadvantages of hard disk backups are that they are easily damaged, especially while being transported (e.g., for off-site backups), and that their stability over periods of years is a relative unknown.Optical storageRecordableCDs,DVDs, andBlu-ray Discsare commonly used with personal computers and generally have low media unit costs. However, the capacities and speeds of these and other optical discs are typically an order of magnitude lower than hard disk or tape. Many optical disk formats areWORMtype, which makes them useful for archival purposes since the data cannot be changed. The use of an auto-changer or jukebox can make optical discs a feasible option for larger-scale backup systems. Some optical storage systems allow for cataloged data backups without human contact with the discs, allowing for longer data integrity.Solid state storageAlso known asflash memory,thumb drives,USB flash drives,CompactFlash,SmartMedia,Memory Stick,Secure Digital cards, etc., these devices are relatively expensive for their low capacity in comparison to hard disk drives, but are very convenient for backing up relatively low data volumes. Asolid-state drivedoes not contain any movable parts unlike its magnetic drive counterpart, making it less susceptible to physical damage, and can have huge throughput in the order of 500Mbit/s to 6Gbit/s. The capacity offered from SSDs continues to grow and prices are gradually decreasing as they become more common.Remote backup serviceAsbroadband Internet accessbecomes more widespread, remote backup services are gaining in popularity. Backing up via the Internet to a remote location can protect against some worst-case scenarios such as fires, floods, or earthquakes which would destroy any backups in the immediate vicinity along with everything else. There are, however, a number of drawbacks to remote backup services. First, Internet connections are usually slower than local data storage devices. Residential broadband is especially problematic as routine backups must use an upstream link that's usually much slower than the downstream link used only occasionally to retrieve a file from backup. This tends to limit the use of such services to relatively small amounts of high value data. Secondly, users must trust a third party service provider to maintain the privacy and integrity of their data, although confidentiality can be assured by encrypting the data before transmission to the backup service with anencryption keyknown only to the user. Ultimately the backup service must itself use one of the above methods so this could be seen as a more complex way of doing traditional backups.Floppy diskDuring the 1980s and early 1990s, many personal/home computer users associated backing up mostly with copying to floppy disks. However, the data capacity of floppy disks failed to catch up with growing demands, rendering them effectively obsolete.

Local Storage Options1. External Hard DriveThese are hard drives similar to the type that is installed within a desktop computer or laptop computer. The difference being that they can be plugged in to the computer or removed and kept separate from the main computer. They typically come in two sizes :Desktop External Hard drive: Uses a 3.5 inch hard drive similar to that used in desktop computers.Portable External Hard drive: Uses a 2.5 inch hard drive similar to that used in laptops.Desktop External Hard Drives are generally cheaper than Portable External Hard Drives for the same storage space. Desktop External Hard Drives and usually faster and more robust.Capacity : 160GB to 3TB (approx 3000GB)Connection: Most common connections to the computer are through a USB 2.0 or USB3.0 connection. May also be available in a SATA or eSATA connectorAdvantages: Very good option for local backups of large amounts of data. The cheapest storage option in terms of dollars per GB. Very reliable when handled with careDisadvantages : Can be very delicate. May be damaged if dropped or through electrical surge

2. Solid State Drive (SSD)Solid State Drives look and function similar to traditional mechanical/ magnetic hard drives but the similarities stop there. Internally, they are completely different. They have no moving parts or rotating platers. They rely solely on semiconductors and electronics for data storage making it a more reliable and robust than traditional magnetic. No moving parts also means that they use less power than traditional hard drives and are much faster too.With the prices of Solid State Drives coming down and is lower power usage, SSDs are used extensively on laptops and mobile devices. External SSDs are also a viable option for data backups.Capacity : 64GB to 256GBConnections: USB 2.0/3.0 and SATAAdvantages: Faster read and write performance More robust and reliable than traditional magnetic hard drives Highly portable. Can be easily taken offsiteDisadvantages: Still relatively expensive when compared to traditional hard drives Storage space is typically less than that of traditional magnetic hard drives.

3. Network Attached Storage (NAS)NAS are simply one or more regular IDE or SATA hard drives plugged in an array storage enclosure and connected to a network Router or Hub through a Ethernet port. Some of these NAS enclosures have ventilating fans to protect the hard drives from overheating.Advantages : Very good option for local backups especially for networks and small businesses. As several hard drives can be plugged in, NAS can hold very large amounts of data Can be setup with Redundancy (RAID) increasing the reliability and/ or read and write performance. Depending on the type of RAID level used, the NAS can still function even if one hard drive in the RAID set fails. Or two hard drives can be setup to double the read and write speed of single hard drive. The drive is always connected and available to the network making the NAS a good option for implementing automated scheduled backups.Disadvantages : Significantly more expensive than using single External Hard Drives Difficult to bring offsite making it very much a local backup hence still susceptible to some events like theft and floods, fire etc

4. USB Thumb Drive Or Flash DriveThese are similar to Solid State Drives except that it is much smaller in size and capacity. They have no moving parts making them quite robust. They are extremely portable and can fit on a keychain. They are Ideal for backing up a small amount of data that need to be brought with you on the go.Capacity: 4GB to 64GBAdvantages: The most portable storage option. Can fit on a keychain making it an offsite backup when you bring it with you. Much more robust then traditional magnetic hard drivesDisadvantages:Relatively expensive per GB so can only be used for backing up a small amount of data

5. Optical Drive (CD/ DVD)CDs and DVDs are ideal for storing a list of songs, movies, media or software for distribution or for giving to a friend due to the very low cost per disk. They do not make good storage options for backups due to their shorter lifespan, small storage space and slower read and write speeds.Capacity CD : 650MB to 900MBCapacity DVD : 4.7GB to 17.08GBAdvantages: Low cost per diskDisadvantages : Relatively shorter life span than other storage options Not as reliable as other storage options like external hard disk and SSD. One damaged disk in a backup set can make the whole backup unusuable.

Remote Storage Options6. Cloud StorageCloud storage is storage space on commercial data center accessible from any computer with Internet access. It is usually provided by a service provider. A limited storage space may be provided free with more space available for a subscription fee. Examples of service providers are Amazon S3, Google Drive, Sky Drive etc.Advantages: A very good offsite backup. Not affected by events and disasters such as theft, floods, fire etcDisadvantages: More expensive then traditional external hard drives. Often requires an ongoing subscription. Requires an Internet connection to access the cloud storage. Much slower than other local backups

There are quite a number of backup types and terms used when it comes to backups of your digital content. This is a compilation of the most common types of backup with a brief explanation of their meaning, common examples, advantages and disadvantages of each backup type.Full BackupFull backup is a method of backup where all the files and folders selected for the backup will be backed up. When subsequent backups are run, the entire list of files and will be backed up again. The advantage of this backup is restores are fast and easy as the complete list of files are stored each time. The disadvantage is that each backup run is time consuming as the entire list of files is copied again. Also, full backups take up a lot more storage space when compared to incremental or differential backups.Read moreIncremental backupIncremental backup is a backup of all changes made sincethelast backup. With incremental backups, one full backup is done first and subsequent backup runs are just the changes made since thelast backup. The result is a much faster backup then a full backup for each backup run. Storage space used is much less than a full backup and less then with differential backups. Restores are slower than with a full backup and a differential backup.Read moreDifferential backupDifferential backup is a backup of all changes made since thelast full backup. With differential backups, one full backup is done first and subsequent backup runs are the changes made since thelast full backup. The result is a much faster backup then a full backup for each backup run. Storage space used is much less than a full backup but more then with Incremental backups. Restores are slower than with a full backup but usually faster then with Incremental backups.Read more...Mirror BackupMirror backups are as the name suggests a mirror of the source being backed up. With mirror backups, when a file in the source is deleted, that file is eventually also deleted in the mirror backup. Because of this, mirror backups should be used with caution as a file that is deleted by accident or through a virus may also cause the mirror backups to be deleted as well.