What the Fallocate command does


This is one of the least used and known commands in Linux and can be very useful for Administrators when building or configuring monitoring of disk space and directory usage. The fallocate command is used for the pre-allocation of blocks to a File. A team of Administrators are on a task to monitor specific directories in multiple servers. How do we test that? Fallocate command helps do this by allocating blocks requiring no I/O to the data blocks. In this article, you will learn “What the Fallocate command does” Please refer to these related guides: How to fix CPU at 100% when nothing is running problem on Windows, what are the advantage of using a 3rd party software for Backup (N2WS by Veeam) over AMI,
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Linux Fallocate Command

NOTE: This command is supported on BTRFS, EXT4, OCTFS2, and XFS filesystems

fallocate --help

Shows the basic usage and command syntax.


To use this command lets check our current disk usage

df -hT

Test by creating a 20GB file

fallocate -l 20G testfile1

view the file size and disk usage


The Fallocate command is similar to the dd command, however, dd exists mostly for older versions of Linux. Top 10 communication software for Mac 2021.

I hope you found this blog post helpful on what the Fallocate command does? Please let me know in the comment section if you have any questions.

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