Averting Disaster - A Guide To Computer Backups (2014)by Brett Howse on May 21, 2014 9:00 AM EST
- Posted in
- IT Computing
- Cloud Computing
We all store more and more of our lives in digital form; spreadsheets, résumés, wedding speeches, novels, tax information, schedules, and of course digital photographs and video. All of this data is easy to store, transmit, copy, and share, but how easy is it to get back?
All of this data can be a harsh reminder that computers are not without fault. For years, storage costs have been dropping while at the same time the amount of storage in any one computer has been increasing almost exponentially. We are at a point where a single hard drive can contain multiple terabytes of information, and with a single mishap, lose it all forever. Everyone knows someone who has had the misfortune of having a computer stop working and wanting their information back.
It’s always been possible to safeguard your data, but now it’s not only necessary thanks to the explosion of personal data, it’s also more affordable than ever. When you think of the costs of backing up your data, just remember what it would cost you if you were to ever lose it all. This guide will walk you through saving your data in multiple ways, with the end goal being to have a backup system that is simple, effective, and affordable. In this day and age, you really can have it all.
It’s prudent at this point to define what a backup is, because there are a lot of misconceptions out there which can cause much consternation when the unthinkable happens, and people who thought they were protected find out they were not.
Backups are simply duplicates of data which are archived, and which can be restored to a previous point in time. The key is the data must be duplicated, and you have to be able to go back to an earlier time. Anything that doesn’t meet both of those requirements is not a backup.
As an example, many people trust their data to network storage devices with RAID (Redundant Array of Independent Disks). Without going into the intricacies of various forms of RAID, none of these Network Attached Storage (NAS) devices are any sort of a backup on their own. RAID is designed to protect a system from a hard disk failure and nothing more. Depending on the RAID level, it either duplicates disks, or uses a calculation to create a parity of the data which can be used to calculate the original value of the data if any part of the data is missing from a failed disk. While RAID is an excellent mechanism to keep a system operational in the event of a disk failure, it is not a backup because if a file is changed or deleted, it is instantly updated or removed on all disks, and therefore there is no way to roll back that change. RAID is excellent for use as a file share, and can even be effectively utilized as the target for backups, but it still requires a file backup system if important data is kept on the array.
Another similar example is cloud storage. Properly configured, cloud storage can be a backup target, and different services can even properly perform backups, but the average person with the average Google Drive or OneDrive account can’t copy their files there and hope they are protected. As with RAID, it is a more robust file storage than any single hard drive, but if you delete a file, or copy over another, it can be difficult or impossible to go back to a previous version.
Both RAID and cloud storage suffer from the same problem – you can’t go back to an earlier time, and therefore are not a true backup. True backups will allow you to recover from practically any scenario – fire, flood, theft, equipment failure, or the inevitable user error. This guide will walk you through several methods of performing backups starting at simple and moving up to elaborate systems that will truly protect your data. These methods work for home and business alike, just the type of equipment will likely differ.
There is some common terminology used in backups that should be defined before we start discussing the intricacies of backups:
- Archive Flag: A bit setting on all files which states whether or not the file has been modified since the last time the flag was cleared.
- Full Backup: A backup of all files which resets the archive flag.
- Differential Backup: A backup of all files with the archive flag set, but it does not clear the archive flag.
- Incremental Backup: A backup of all files with the archive flag set which resets the archive flag.
- Image or System Based Backup: A complete disk level backup which would allow you to image a machine back to a previous state.
- Deduplication: A software algorithm which removes all duplicate file parts to reduce the amount of storage required.
- Source Deduplication: removing duplicate file information from files on the client end. This requires more CPU and memory usage on the client, but allows for a much smaller file size to be transferred to the backup target.
- Target Deduplication: removing duplicate file information from files on the target end. This saves client CPU and memory usage, and is used to reduce the amount of storage space required on the backup target.
- Block Level: A backup or system process which accesses a sequence of bytes of data directly on the disk.
- File Level: A backup or system process which accesses files by querying the Operating System for the entire file.
- Versioning: A list of previous versions of a file or folder.
- Recovery Point Objective (RPO): The amount of time since the last backup deemed safe to lose in a disaster scenario. For example, if you perform backups nightly, your RPO would be the previous night’s backups. Anything created in between backups is assumed to be recoverable through other methods, or an acceptable loss.
- Recovery Time Objective (RTO): The amount of time deemed acceptable between the loss of data and the recovery of data. For home use, there’s really no RTO but many commercial companies will have this defined either with in-house IT or with a Service Level Agreement (SLA) to a support company.
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Brett Howse - Wednesday, May 21, 2014 - linkBacking up 6 TB is not an issue unless you modify all 6 TB between each backup, and even then it's really not a big deal. You can stand up 6 TB of network storage for not very much money.
It all comes down to whether or not the data is important to you.
Gigaplex - Wednesday, May 21, 2014 - linkBacking up 6TB is most definitely an issue. Local backups require several hundred dollars worth of additional hardware (closing in on $1000 depending on the type of NAS). Off site is even harder, cloud backup isn't even an option so you need some kind of sneakernet.
Brett Howse - Wednesday, May 21, 2014 - linkGigaplex, what I'm saying is that it's not very difficult to achieve this. If you have 6 TB of data that's worth backing up, then I assume that data's worth the couple hundred dollars in hardware required to back it up.
Once you move into this kind of data storage requirement, obviously cloud backup is going to get expensive, but there are other options.
You just have to decide if it's worth backing up, or perhaps a subset of the data is worth backing up.
Before you can dismiss any backup, all you have to do is decide how much the data is worth to you.
kamiyo - Wednesday, May 21, 2014 - linkThere's SyncBack which has multiple levels of features, the lowest being free. I guess it's technically not a backup solution, but more of a backup helper, but it allows you to schedule and backup specific files/folders (or whole drives) and much more. It was recommended by a friend
Impulses - Wednesday, May 21, 2014 - linkSyncBack and MS SyncToy are both decent freeware options for the simpler backup jobs.
SeanFL - Friday, May 23, 2014 - linkSyncToy did not scale well to a hundred thousand picture files I had years ago...it starting creeping extremely slow even on incremental backups. Maybe there was some improvement somewhere? Didn't see any new version last time I looked.
dstarr3 - Wednesday, May 21, 2014 - linkI swear by SyncBack. It's a ridiculously simple way to manage file backups on an external drive.
BeethovensCat - Sunday, May 25, 2014 - linkSyncToy has been reliable for me. But lately I have shifted to FreeFileSync for syncs to my external HDDs. Seems to be faster and work better (sometimes the total file sizes on my internal backup drive and the external HDD differed with SyncToy - set to Echo - never figured out why). I have confidential work files on my external HDD (WD Passports) so I encrypt everything with TrueCrypt. Can afford to loose a HDD, but wouldn't like the data to end up in the wrong hands.
hasseb64 - Wednesday, May 21, 2014 - linkFor nonprofessionals: Avoid RAID!
BeethovensCat - Sunday, May 25, 2014 - linkNot so sure that is true. I have 'played' with RAID 0 for the last ten years and never (fingers crossed) had an array fail. Neither HDD or SSD. I try to run Syncs 2-3 times per week to avoid data loss should it happen. Am using the in-built Intel RAID controllers on Asus motherboards. Seems to be very reliable.