notice no HDD space is consumed with this command: # BEFORE With this you could actually create an arbitrary large file, regardless of the available space on the device, as it creates a "sparse" file.įor e.g. Will create a 10 M file instantaneously (M stands for 1024 1024 bytes, MB stands for 10001000 - same with K, KB, G, GB.)ĮDIT: as many have pointed out, this will not physically allocate the file on your device. Most Linux systems also have fallocate, which only works on certain file systems (such as btrfs, ext4, ocfs2, and xfs), but is the fastest, as it allocates all the file space (creates non-holey files) but does not initialize any of it. It's included in xfsprogs (for Debian/Ubuntu) or similar named packages. Most Linux systems have xfs_mkfile which works exactly the same way, and not just on XFS file systems despite the name. Mkfile is derived from SunOS and is not available everywhere. Without the -n option, the space is zero-filled, which means writing to the disk, which means taking time. With the -n option the size is noted, but disk blocks aren't allocated until data is written to them. Try mkfile myfile as an alternative of dd. Prealloc 10Gigfile 10737418240 Explanation Xfs_mkfile 10240m 10Gigfile Linux & and some filesystems (ext4, xfs, btrfs and ocfs2)įallocate -l 10G 10Gigfile OS X, Solaris, SunOS and probably other UNIXes So, when you use fallocate to create a 20 GB virtual drive space, you really do get a 20 GB file (not a "sparse file", and you won't have bothered to write anything to it - which means virtually anything could be in there - kind of like a brand new disk!) E.g.: fallocate -l 10G gentoo_root.img E.g.: truncate -s 10G gentoo_root.imgįallocate is the final - and best - choice for use with VM disk allocation, because it essentially "reserves" (or "allocates" all of the space you're seeking, but it doesn't bother to write anything. Thus, when you use truncate to create a 20 GB drive for your VM, the filesystem doesn't actually allocate 20 GB, but it cheats and says that there are 20 GB of zeros there, even though as little as one track on the disk may actually (really) be in use. Essentially, a sparse file is a section of disk that has a lot of the same data, and the underlying filesystem "cheats" by not really storing all of the data, but just "pretending" that it's all there. But that is because it creates a "sparse file". Truncate is another choice - and is likely the fastest. E.g: dd if=/dev/zero of=./gentoo_root.img bs=4k iflag=fullblock,count_bytes count=10G (Want to make it take even longer? Use /dev/random instead of /dev/zero! Then you'll use CPU as well as I/O time!) In the end though, dd is a poor choice (though essentially the default used by the VM "create" GUIs). And that initialization is what takes up so much I/O time. Unfortunately, the answer is not as straight-forward as one might assume.ĭd is the obvious first choice, but dd is essentially a copy and that forces you to write every block of data (thus, initializing the file contents). Hi guys,I have a problem with a fortigate 100f, when a websited is blocked, it is not showing the webfilter error message, it is only saying connection reset.Investigating a little bit, i found out that disabling app control will do the trick.Is there any.This is a common question - especially in today's environment of virtual environments. Fortiguard webfilter block message Security.Simple question for all you networking experts.ĭo I run all RJ45 wall socket points all the way back to the. In the near future we are building a new office block, 2 storey building, separate meeting rooms etc. Snap! - Space Email, Moon Landing Delay?, End of the World, Car to Home Power Spiceworks Originalsįlashback: August 9, 1898: Diesel Engine Patented (Read more HERE.)īonus Flashback: August 9, 1991: The First E-mail From Space (Read more HERE.). I told him that plan was to move it to a new fileserver and shar. new IT boss saying move it to sharepoint and setup permissions for each group. We have good amount of data (900 gb) sitting on one user's computer, its shared and mapped to other users.
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