{"id":49112,"date":"2023-03-25T13:57:13","date_gmt":"2023-03-25T09:57:13","guid":{"rendered":"https:\/\/www.msp360.com\/resources\/?p=49112"},"modified":"2024-08-14T11:54:48","modified_gmt":"2024-08-14T07:54:48","slug":"image-based-backup-restoration-how-to-recover-a-backup-to-a-disk-of-a-smaller-size","status":"publish","type":"post","link":"https:\/\/www.msp360.com\/resources\/blog\/image-based-backup-restoration-how-to-recover-a-backup-to-a-disk-of-a-smaller-size\/","title":{"rendered":"Image-Based Backup Restore: Recover a Backup to a Disk of a Smaller Size"},"content":{"rendered":"

Scheduled full-system backup is a must in the production environment. If something goes wrong with a system or your computer, you can restore the system to a working state on a working machine and get back to your tasks without downtime. Usually, the recovery process goes smoothly; you just deploy your old system on a destination computer and that\u2019s all. However, there are some use cases that require additional actions.<\/p>\n

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One such use case is when you need to restore your system to a disk of a smaller size. For example, when you need to move from HDD to SSD, or your alternate computer has a smaller disk (one of our clients\u2019 situation). Below, our system administrator and solution architect explain how to solve this issue when creating an image-based backup in MSP360 Managed Backup Service<\/a> on Windows OS. All the tools used are Windows built-ins.<\/p>\n

Restoring an Image-Based Backup to a Smaller Disk<\/h2>\n

The data on disk is stored in sectors \u2013 the smallest chunks of data on a hard disk. Each file has many sector units assigned to it. These sectors are not located near each other; they can be scattered around the disk. This is called fragmentation, and it is fragmentation that makes it difficult to shrink a partition to the desired size during restore.<\/p>\n

It is also necessary to know that the image-based backup<\/a> plan in Managed Backup Service backs up data by keeping the information about the placement of sectors on the drive, as well as the start offset of disk partitions. Thus, the backup preserves the disk fragmentation as is, with all its inefficiency. If the disk that you\u2019re going to use for system recovery is smaller than the original one, there won\u2019t be enough space for your fragmented system. Here are some measures that will help you to shrink the system before backing it up.<\/p>\n

Tip 1. Defragmentation<\/h3>\n

Defragmentation picks up the file\u2019s fragments and joins them all together, one by one. After it completes, the files in your computer\u2019s storage become sequences of data blocks, and all the blocks that relate to a single file are located near each other. When possible, defragmentation also stocks all the \u201cbusy\u201d blocks in a pile, dividing the disk into two parts: one that\u2019s busy with data and one that\u2019s free. Not only does this reduce the size of your system, but it also speeds up your computer. To run defragmentation, open the Start menu and type \u201cdefrag\u201d. Windows will show the appropriate option: Defragment and Optimize Drives.<\/p>\n

Please note: defragmentation can change the placement of a lot of sectors, even the ones that are for non-fragmented files. In this case, the next block-level backup can grow in size.<\/p><\/blockquote>\n

\"Disk
\nHowever, in most cases, defragmentation is not enough to shrink a volume (but it is worth doing it to start with anyway).<\/p>\n

Tip 2. Disabling System Files<\/h3>\n

There are system files that can be placed anywhere on the system partition, even in the middle of it, regardless of the space used. These files might appear as an obstacle to system shrinking. If the system is working properly, system files can be temporarily <\/b>disabled. After a successful shrink or restore job, they must be re-enabled. Here is a list of these files:<\/p>\n