Commands tagged Filesystem (34)

  • Particularly useful if you're mounting different drives, using the following command will allow you to see all the filesystems currently mounted on your computer and their respective specs with the added benefit of nice formatting. Show Sample Output

    mount | column -t
    thechile · 2009-03-20 14:18:56 9
  • Curious about differences between /bin, /usr/bin, and /usr/local/bin? What should be in the /sbin dir? Try this command to find out. Tested against Red Hat & OS X

    man hier
    haivu · 2010-01-26 16:31:05 2
  • Ever ask yourself "How much data would be lost if I pressed the reset button?" Scary, isn't it? Show Sample Output

    grep ^Dirty /proc/meminfo
    h3xx · 2011-08-24 08:48:49 8
  • In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point. Show Sample Output

    (mountpoint -q "/media/mpdr1" && df /media/mpdr1/* > /dev/null 2>&1) || ((sudo umount "/media/mpdr1" > /dev/null 2>&1 || true) && (sudo mkdir "/media/mpdr1" > /dev/null 2>&1 || true) && sudo mount "/dev/sdd1" "/media/mpdr1")
    tweet78 · 2014-04-12 11:23:21 3
  • Create a temporary file that acts as swap space. In this example it's a 1GB file at the root of the file system. This additional capacity is added to the existing swap space. Show Sample Output

    sudo dd if=/dev/zero of=/swapfile bs=1024 count=1024000;sudo mkswap /swapfile; sudo swapon /swapfile
    dcabanis · 2009-05-27 21:10:50 1
  • since fuse mounts do not appear in /etc/mtab (fuse can't write there, dunno if it would if it could) this is propably a better way.

    column -t /proc/mounts
    unixmonkey5049 · 2009-08-09 17:00:41 2
  • Finds all directories containing more than 99MB of files, and prints them in human readable format. The directories sizes do not include their subdirectories, so it is very useful for finding any single directory with a lot of large files. Show Sample Output

    du -hS / | perl -ne '(m/\d{3,}M\s+\S/ || m/G\s+\S/) && print'
    Alioth · 2009-03-25 18:06:53 1
  • This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables. Show Sample Output

    dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
    rodolfoap · 2013-01-31 01:38:30 5
  • Before doing this, back-up all data on any ext3 partitions that are to be converted to ext4. After running previous command you MUST run fsck, is needed to return the filesystem to a consistent state. fsck -pDf /dev/yourpartition Edit /etc/fstab and change the 'type' from ext3 to ext4 for any partitions that are converted to ext4.

    tune2fs -O extents,uninit_bg,dir_index /dev/yourpartition
    starchox · 2009-06-23 17:42:01 1
  • the middle command between the ; and ; is the vi commands that insert that line into the last line of the file, the esc with the carets is literally hitting the escape key, you have to have the smbfs package installed to do it, I use it to access my iTunes music on my mac from my linux PC's with amarok so I can play the music anywhere in the house. among other things, it allows you to access the files on that share from your computer anytime you're on that network.

    sudo vi /etc/fstab; Go//smb-share/gino /mnt/place smbfs defaults,username=gino,password=pass 0 0<esc>:wq; mount //smb-share/gino
    GinoMan2440 · 2009-04-02 16:04:35 3
  • To create directory, use: tempdir=$(/bin/mktemp -d)

    takeshin · 2010-06-05 21:36:49 0
  • When a fs hangs and you've just one console, even # ls could be a dangerous command. Simply put a trailing "&" and play safe

    ls /mnt/badfs &
    ioggstream · 2009-06-30 14:40:22 0

  • 2
    grep -v rootfs /proc/mounts > /etc/mtab
    ohe · 2014-01-21 14:28:12 0
  • use the locate command to find files on the system and verify they exist (-e) then display each one in full details. Show Sample Output

    locate -e somefile | xargs ls -l
    nadavkav · 2009-08-23 13:16:59 0

  • 1
    tune2fs -c -1 -i 0 /dev/VG0/data
    christian773 · 2010-05-29 08:20:35 0
  • This one-liner is for cron jobs that need to provide some basic information about a filesystem and the time it takes to complete the operation. You can swap out the di command for df or du if that's your thing. The |& redirections the stderr and stdout to the mail command. How to configure the variables. TOFSCK=/path/to/mount FSCKDEV=/dev/path/device or FSCKDEV=`grep $TOFSCK /proc/mounts | cut -f1 -d" "` MAILSUB="weekly file system check $TOFSCK " Show Sample Output

    ( di $TOFSCK -h ; /bin/umount $TOFSCK ; time /sbin/e2fsck -y -f -v $FSCKDEV ; /bin/mount $TOFSCK ) |& /bin/mail $MAILTO -s "$MAILSUB"
    px · 2010-10-24 00:35:23 1
  • Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.

    mount -o remount,ro /dev/foo /
    vlan7 · 2010-10-30 03:51:53 1
  • Clone a root partition. The reason for double-mounting the root device is to avoid any filesystem overlay issues. This is particularly important for /dev. Also, note the importance of the trailing slashes on the paths when using rsync (search the man page for "slash" for more details). rsync and bash add several subtle nuances to path handling; using trailing slashes will effectively mean "clone this directory", even when run multiple times. For example: run once to get an initial copy, and then run again in single user mode just before rebooting into the new disk. Using file globs (which miss dot-files) or leaving off the trailing slash with rsync (which will create /mnt/target/root) are traps that are easy to fall into.

    mount /dev/root /mnt/root; rsync -avHX /mnt/root/ /mnt/target/
    jharr · 2011-08-24 14:29:17 0

  • 1
    mount -o sb=98304 /dev/sda5 /mnt/data5
    rugina · 2013-06-25 08:50:44 2
  • I added -S to du so that you don't include /foo/bar/baz.iso in /foo, and change sorts -n to -h so that it can properly sort the human readable sizes.

    du -Sh | sort -h | tail
    pdxdoughnut · 2013-11-27 17:50:11 0
  • XX is your device partition number like /dev/sdc1 . to see how many inodes your partition have type: df --inodes (or df -i) Default formatting with ext4 would create small inode count for the new partition if you need big count of inodes is the fstype news the correct one. in debian you can see which fstype exists as template in: vim /etc/mke2fs.conf if you format default ext for a partition size with 1TB you would get 1 Million inodes (not enough for backupStorages) but if you format with fstype news you would get hunderd of millions of inodes for the partition. you have tune /etc/sysctl.conf also with following sysconfig parameters fs.file-max = XXX fs.nr_open = XXX where XXX is the count of max inodes for whole system

    mkfs.ext4 -T news /dev/sdcXX
    aysadk · 2019-07-02 13:31:23 0

  • 0
    find /home/fizz -type f -printf '%TY-%Tm-%Td %TT %p\n' | sort
    fizz · 2009-05-20 10:45:39 2
  • Useful for analyzing disk usage. If you prefer GUI try or Show Sample Output

    du -aB1m|awk '$1 >= 100'
    karatatar · 2009-08-01 20:16:33 1
  • Iozone with a file of 2GB, 64KB record size, write/rewrite and read/re-read test, using just one thread. Show Sample Output

    iozone -s 2g -r 64 -i 0 -i 1 -t 1
    w00binda · 2009-11-19 10:43:54 0

  • 0
    du -h / | grep -w "[0-9]*G"
    pashutinsky · 2011-07-23 19:02:11 0
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cd to (or operate on) a file across parallel directories
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Found how how much memory in kB $PID is occupying in Linux
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Get a range of SVN revisions from svn diff and tar gz them
Handy when you need to create a list of files to be updated when subversion is not available on the remote host. You can take this tar file, and upload and extract it where you need it. Replace M and N with the revisions specific to yours. Make sure you do this from an updated (svn up) working directory.

Selecting a random file/folder of a folder
Also looks in subfolders

urldecoding with one pure BASH builtin
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Printout a list of field numbers (awk index) from a CSV file with headers as first line.
Useful to identify the field number in big CSV files with large number of fields. The index is the reference to use in processing with commands like 'cut' or 'awk' involved.

auto complete arguments
Use it for command like : mkdir, chown, ls, less...

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