Restoring from Mac and PC backups. John Steele (PC) Mike Burton (MAC)

Transcription

1 Restoring from Mac and PC backups John Steele (PC) Mike Burton (MAC) 1

2 Structure Overview of backup and restore strategies Why you should backup data and ways in which the backups and restores work Windows backup tools and techniques MAC backup tools and techniques 2

3 What is Restore - is it important? Do you have any important data on your computer? What would be the impact on your life it you were to lose it? Examples that could cause loss include: Your computer could be stolen Your house could have a fire Your computer might die - your Hard Disk might crash You may accidentally delete a file You may have Malware that deletes or encrypts your data To be able to recover your data you must have a Backup to restore it from! 3

4 Disk Drive Internal View 4

5 Disk Drive Tracks and Sectors Each sector is a fixed size is the smallest unit of data A cluster contains a fixed number of sectors and is the unit of data allocation within the Operating System 5

6 Disk Partitions Disk partitioning or disk slicing is the creation of one or more regions on a hard disk or other secondary storage, so that an operating system can manage information in each region separately. With Windows separate disk partitions can be allocated drive letters and accesses as if they were separate physical drives. The partition sizes can be changed (larger or smaller) with programs such as EASEUS or (with limitations) Drive Manager on Windows systems 6

7 Example Partition table 7

8 What are backups for Backups help to protect you against the loss of data If you do not keep ANY important data on your computer then you have no need of backup! Assuming that you decide that some form of backup is a good thing we need to consider what sorts of backups are available to you and when you should use each type You need to take backups regularly as you are vulnerable to data loss between backups 8

9 Types of backup Types of backup Clone of your hard disk Backup of each partition of your disk Backup of selected folders and files For each type backup you need to consider how to keep your backup up to date How often do you back up, hourly, daily, weekly, monthly, annually, when you feel like it or remember! We will look at each type of backup and consider the options 9

10 Full Backup Copies the full content to backup Self contained does not depend on other backup copies Slow and takes up a lot of space Need to take full backups periodically 10

11 Differential Depends on having a prior full backup Backs up differences between the most recent full backup and the current state Quick for first differential backup but gets slower and bigger as changes accumulate Restoration only requires two file sets: Prior full backup Most recent differential backup file set Note that this will increase in size each time it is taken 11

12 Incremental Depends on having a prior full backup Backs up files that have changed since most recent full or incremental backup Time taken only depends on how many files have changed since last backup Restoration requires: Prior full backup All of the incremental files between the last full backup and the date of restoration Note each incremental file set needs to be applied in order with the oldest first 12

13 Incremental vs Differential 13

14 Backup type = Clone Binary Image of the entire disk drive Can save space on backup by eliminating zero sectors Some software may be able to perform incremental or differential backups Benefits Can be relatively fast Limitations Typically can only restore to an IDENTICAL drive with the same number of heads, and same track layout May not be possible to buy a new drive if the drive has failed doe to obsolescence Recovery of individual files depends on the software Only intended for (re)building a computer, or a set of computers, to a known baseline 14

15 Backup type = Image Binary copy of disk partitions to storage Partitions can be restored to different drives and the disk sizes do not have to match Individual partitions have different functions and backup strategies can be tailored accordingly The target partition can be bigger that the original and all partitions do not need to restored to the same physical drive Good use is for taking an image of all partitions on a computer before a major OS update Can do incremental backups but will probably include all OS changes unless care is taken 15

16 Backup of folders and files This approach is in general best for user data and NOT for OS backup It can be used in many ways and have different impacts on ease of recovery Traditional backups strategies use a periodic full backup of (selected) folders. Some non critical data can be skipped (e.g. temporary files) Intermediate backups of changed files in between full backups Either differential or incremental strategies can be used 16

17 Recovery Strategies Clone Recover to brand new or reformatted disk. Overwrites all data currently present on drive Image Recover partition to a new or existing partition Overwrites all data currently on that partition Some image software enables individual files to be recovered File Restores all folders and files on existing partition Individual files or folders can be also be recovered 17

18 Recovery strategies Full backup every time No other files are needed Differential backup Most recent full backup Most recent differential backup Incremental backup Most recent full backup All incremental backups since last full backup Must be applied in the order of oldest first 18

19 End of Introduction To follow Windows Backup and restore MAC Backup and restore 19

20 Mac TimeMachine TimeMachine does a Full File backup initially Hence it takes an hour or two Thereafter it does Incremental backups of changed files BUT it adds links to the un-changed files So we can see a full view of all files at that point in time. 20

21 Viewing TimeMachine Backups Because they are File-based we can browse them with Finder just like any files / folders No need for special software to interpret the backup data To restore files or folders we use Enter Time Machine Nice space-age view of our files going back in time Also integrates with some apps eg Mail, to view or restore the situation from previous point in time. 21

22 Viewing TimeMachine Backups... Can also restore entire system, as we saw earlier Handles open & locked files as standard So no need for Image backup Other useful recovery options at boot: Full restore from any backup Choose boot device Internet recovery, in case Mac's recovery partition damaged (a big download but a useful fallback) Target disk mode- Makes this Mac behave like a remote / USB disk, so as to copy its data to another Mac 22

23 Time machine Data 23

24 Windows 10 Tools and Features System Restore IF ENABLED Allows you to revert to a previous configuration e.g. to remove a failed OS or program update Often applied automatically on Windows updates Takes up space on your computer Does not work for user files! Windows File History See later 24

25 Windows Tools - File Windows file history Windows can be set to automatically back up files to a permanently attached file store It runs regularly and backs up any changes It uses the file name to identify the date and time of each backup There is no limit I could find on how many copies to keep only a fixed size limit in the destination folder and then it appears to delete the oldest I tried it for several months and it filled up my NAS store and have now removed it Recovery is manual and would need to recover each file separately 25

26 Windows Tools - Disk/Partition This is not an exhaustive list These are the programs I have been using for years Disk Clone (not recommended for routine backup) Macrium Reflect EaseUS Partition Master Free 12.8 Disk/Partition Imaging Macrium Reflect Supports incremental backups Supports bare metal restore to dissimilar drives 26

27 Windows Tools - File Syncback Designed to mirror one set of files with another similar set Deletions from backup will delete copy in master if not careful Can copy only changed files Does NOT produce full/differential/incremental file sets Does not use Volume Shadow feature to enable open files to be copied (unless you pay for the professional version) Good program for what it is designed for Does not have the features for a full backup solution as it does not keep a set of previous versions 27

28 Windows Tools - File Cobian Rather old program that has not been maintained BUT WORKS Excellent for a cycle of Full backup + set of differential or incremental changes Will switch to a full backup after n incremental backups Will keep a configured number of full backups + incremental sets and automatically deletes out of date ones Designed to run on a schedule if you have a permanently connected backup device Uses Volume Shadow Copy service to backup files that are open Recovery is manual using file copy and may need to recover the last full copy and all incremental (or latest differential) copies manually Set and forget! 28

29 Cloud Does this provide backup? A cloud service can be used to supplement any of the other backup strategies This approach is very useful for the most important data but probably impractical for large volumes of data. I recommend it is used in addition to some other form of backup You use it like any other folder and the magic happens in the background Cloud storage usually keeps multiple versions so you can go back to an earlier one is a file is lost or corrupted 29

30 Cloud Providers Many free providers exist All now impose limits on free storage space provided typically 2 Gbyte Examples include: DropBox Google Drive OneDrive SpiderOak TeamDrive I use TeamDrive in preference to DropBox, OneDrive or GoogleDrive TeamDrive encrypts your file on the PC (or phone) BEFORE uploading With TeamDrive you need the paid for version to automatically limit the number of versions of each file kept 30