Commands tagged ext4 (5)

  • Migrate existing Ext3 filesystems to Ext4

    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.


    5
    tune2fs -O extents,uninit_bg,dir_index /dev/yourpartition
    starchox · 2009-06-23 17:42:01 14
  • Get creation date of a file on ext2-3-4 fs

    Return the creation date of a file on ext2, 3, 4 filesystems, because stat command won't show it. Useful on ubuntu, debian, and else Show Sample Output


    3
    debugfs -R "stat <$(stat --printf=%i filename)>" /dev/sdaX | grep crtime
    pggx999 · 2015-04-09 01:23:56 10
  • Format partition with ext4 but without a journal

    For slow flash memory (cheap thumb drive), ext4 is the fastest stable file system for all use cases with no relevant exception: http://www.linuxplanet.com/linuxplanet/tutorials/7208/1 Since we can usually dispense with the benefits of a journal for this type of storage, this is a way to achieve the least awful I/O-speed. Disabling the journal for an existing ext4 partition can be achieved using tune2fs -O ^has_journal /dev/sdXN Note that it is often recommended to format removable flash media with ext2, due to the lack of a journal. ext4 has many advantages over ext2 even without the journal, with much better speed as one of the consequences. So the only usecase for ext2 would be compatibility with very old software.


    2
    mke2fs -t ext4 -O ^has_journal /dev/sdXN
    michelsberg · 2013-02-15 17:24:02 7
  • create ext4 filesystem with big count of inodes

    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


    1
    mkfs.ext4 -T news /dev/sdcXX
    aysadk · 2019-07-02 13:31:23 39
  • Find out the installation time of a linux system (when installed in a ext2/3/4 file system)

    Find out the earliest installation time of a linux system by getting the / filesystem creation time. This example is only valid the os is installed on an ext2/3/4 filesystem.


    0
    tune2fs -l $(df -P / | awk 'NR==2 {print $1}') | sed -n 's/^.*created: *//p'
    forcefsck · 2012-05-31 12:12:35 4

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