I have been working with a computer for at least the last 15 years (my first computer was an Intel 286) and since my early use I have always been worried about how to safely store my data
My first back up support was just a small box packed with CDs, each of them carefully labelled to keep record of their content.
Fortunately (or unfortunateley depending of the point of view) in those days there was no digital pictures or .mp3 files, so most files did not have enormous size.
After few years I moved to 100MB Yomega Zip drives, which to be honest did not get much use.
Later DVDs and external USB 2.0 hard drives came out, with the latter quickly ranking among my favourite back up support.
The advantages of this data storage device are
1) direct data access, not sequential (I couldn't put up with tapes, do you remember the lengthy loading time of the Commodor 64!)
2) low $/Mb cost
3) Portable and compatible with most of today's computers (at least if you pick up one with an external USB 2.0 interface)
WHAT KIND OF BACK UP STRATEGY TO USE?After choosing the type of hardware storage device, the next important choice is to select the correct software
to back them up quickly and reliably.
There are mainly two type of back up needs
1) System disk backup
2) Personal data backup
System Disk Back upFor system disk back up, my favourite choice on Wndows XP is BartPE and DriveImage XML, the latter available as an add-in for BartPE.They are free of charge, just google them for additional information.
Recently, I have bought a new Pc with Windows 7 64bit professional edition installed and I have started to look for new software compatible with this OS.
After few days of search I ended up with this final list
1) BootIt Ng
2) Macrium Reflect
3) Paragon HDM 2010.
Without going into much details (I can do it on request) I found the Paragon HDM 2010 to be the best one.
One of the most impressive features of this sofware is its WinPE Recovery ISO image.
If something goes wrong with your system disk (hard disk failure, virus attack, ...) just put the WinPE disk image provided by Paragon on either a DVD or USB pen drive, boot the system and restore your disk. You can create full back up, incremental and differential images.
The Recovery software is very friendly, and impressively easy to use. It looks like the one installed on your windows machine, so there is no additional effort to learn it.
Tu summarize these are its main strengths::
- WinPE recovery CD interface is basically the same as the full version one
- The recovery image can be put on a bootable CD/DVD or USB Pen drive! (Very new capatily in these days)
- You can restore images on Hard drives whose size is less than the image been restored. However in this case the recovery process is much slower.
- Partitions can be created, resized (with no data loss) and formateted with just few clicks
- All the operations can be performed in simulation mode, so there is no risk of making any mistakes
In addition to that, HDM Suite can also create file based differential and incremental backups, and sector based differential backup (very useful for a system recovery strategy).
Personal data backupOnce we have made a system recovery image, we need to turn our attention to create a full back up of our data. In this contest data is: photos, videos, .doc., .pdf, .xls, power point presentation,... anything that you cannot just download from the web.
The first software I have used to create recovery copies of all my data is Allway sync. In a matter of half an hour I realized how much quicker my backup strategy could have been if I had used it since the beginning.
My first naive strategy was just to copy and past my files from my internal hard drive to the external storage device (DVD/Hard disk) each time. That was fine at the beginning but as the time went by, the overall amount of data to be saved increased and the process was getting time consuming. I wished I had a software that could just spot the differenced between the recovery copy and the new data on the main drive, and just update the new/changed files. The solution was a synchronization software: Allways sync.
The main draw back of this very simple strategy is that if you delete by mistake a file or you need any old file version, you will not be able to restore it. To be honest in more than ten years I have never had the necessity to restore any old copy or deleted file. We will see later how to sort this issue.
The are different stretegies that can be used to make safe copies of your data
Tu sum up the most important
- Mirroring
- Backup
- Differential backup
- Incremental Backup
- versioning
MIRRORING
Mirroring is the exact file copy of the source folders to the destination.
If a file is deleted from the source, it will be deleted in the destination. This is called "propagate deletions"
If a file is modified from the source, it will be copied to the destination. This is called "propagate modifications"
So the mirroring is a file copy with propagation of deletions and modifycations. There is no chance to recover
any old/deleted files.
BACKUP
Backup is a copy with only propagation of modifications. This means that deleted files can be recoverd, but there is no chance to recover old file versions
INCREMENTAL BACKUP
Incremental Backup is based on a initial Full Backup, and a series of additional backups that record on the destination only the changes that have occured since the last incremental backup.
This is how it works
1) Full Backup source: files a,b,c destination: files a,b,c
2) Incremental backup source: files a,b,c,d destination :just add "d"
3) Incremental backup source: files a,b,c,d,e destination: just add "e"
4) Incremental backup source: files a',b,c,d,e destination: just add modificatioins to file a, but you will not loose the initial file that is stored in the Full Back.
5) Incremental backup source: files a', ,c,d,e destination: do nothing
With this strategy, you can recover both old files and deleted ones. In addition if you set the Incremental Backup to run everyday, you can restore the source on a specific day in the past.
The major advantages are
1)You can restore the source at any specific point in time. This is useful if you have hundreds of files that change every day, and you need to restore the system at a specific point in the past.
The major draw-backs are
2) To restore the files as of today, you need to first restore the initial full back-up and then, one by one all the incremental back-up in strict order.
3) It is more difficult to set up and maintain than differential back up and mirroring.
DIFFERENTIAL BACKUP
Differential Backup is based on a initial Full Backup, and a series of additional backups that record on the destination only the changes that have occurred since the First full backup.
This is how it works:
1) Full Backup: source: files a,b,c destination: files a,b,c
2) Differential backup source: files a,b,c,d destination : just add "d" file
3) Differential backup source: files a,b,c,d,e destination: just add "d" and "e" file
4) Differential backup source: files a',b,c,d,e destination: just add "d", "e" and "a'" (the original "a" file is stored in the original full backup)
5) Differential backup source: files a', ,c,d,e destination: do nothing
In this case to restore the system to the last state only two files are needed - the original Full back up and the last differential back up. The differential back up requires more space the the incremental one, but less space than the Full backup strategy.
VERSIONING
This is my favourite. Versioning stores one or more copies of any files that has been modified or deleted, keeping in memory the modify/delete date. In addition, the final user has the option to restore a specific version on the source drive.
To be more precise I use the mirroring + versoning approach.
The major advantages are
1) To restore the system to the current state is very easy. This is because, the current state is the default one, Additional steps needs to be taken only if any versioned file needs to be restored.
2) Easy to set up
The major draw-backs are
2) It it difficult to restore the system at a particular point in time, especially if many files are subject to change.
In my opinion for a domestic user, mirroring + versioning is the favourite choice, because it is very easy to set up and keep it running. If you do not have the need to restore the system as it was in a particular point in the past (and this is unusual for a domestic user) this is the preferred solution.
In the rest of this article we will have a look at Allway sync and SynbackPro.