Questions tagged [superblock]
Use for question about the special metadata "super block" of filesystems.
84 questions
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Why is ext3 superblock data seemingy not updated after mount?
I had the idea to compare the system clock with the data of the last superblock update when booting (as traditional UNIX systems did).
However it seems the superblock (or at least it's write time) is ...
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How many Group Descriptor is there in GDT of Ext4?
GDT = Group Descriptor Table ; GD = Group Descriptor. I'm trying to figure out how many bytes I need to read after the superblock to extract the entire GDT, because it's needed for a program I'm ...
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Accidentally ran mkswap on ext4 fs
I accidentally used mkswap on a unmounted 2 TB data partition of a hard drive (not an SSD), while I was on a live USB session. I did not run swapon as I immediately realized what I had just done.
I ...
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Disk error by partioning dual boot and running fsck -b
so after I partitioned with mini partion tool the drive containing Linux and windows 11 broke the windows so I hoped on linux trying to fix it but the linux partition sustained some damage too it ...
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Corrupt EXT4 filesystem, backup superblock no dice
I am a novice linux user, for some time. I need some help with recovering a corrupted EXT4 filesystem.
Ideally, I would like to recover the filesystem intact. The drive in question is 'sda'. The ...
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XFS superblock not found
I had an old drive beginning to fail and my backups were no good apparently.
I got a new drive larger than the failed one and was able to ddrescue it over, with bad/missing superblocks of course.
...
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Unix ext2 superblock - file system creation date
I am trying to find the creation date on an ext2 file system. I seem to get a current date using dumpe2fs.
The problem is that the original ext2 superblock specification does not contain such ...
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Raid can be assembled but not mounted, issue is with the superblock
I moved tow drives which where mounted in a raid1 to another to a new system to be mounted there. One drive was detected instantly, the other one had issues with the super blocks.
After reading Kevin ...
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Recover ext4 partition with bad superblock? (Failed after resizing, backup magic numbers don't work)
Background
Had a Linux root ext4 partition that I needed more space; cleared it from my Windows install, and then modified the remaining stuff on KDE's partition manager on a live usb.
I'm not ...
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How did my ext3 superblocks get so messed up? And how to fix them?
I've recently found an old external hard disk and I have no idea what's on it. There was only one partition, encrypted with dm-crypt. Luckily I still remembered some of the passphrases that I used ...
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Fedora boot errors after a update
I did an update on my Fedora USB stick and after that there were errors booting and I got into ermergency mode.
Error:
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Bad superblocks after partition manager error, any way to solve?
Alright so I was using Lubuntu to create a swap partition for my KDE Neon system and I used KDE Partition Manager (it came preinstalled with Lubuntu).
It shrinked the drive in 8GB and sat there for a ...
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Rebuilding directory tree (and/or inodes)
Problem
My Armbian based Orange Pi webserver crashed (probably because of a power loss). I thought it would be fine since ext4 is more resilient and it usually has been in the past, but for some ...
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How does the OS access files stored on the hard disk?
I know the first thing the OS accesses on the harddisk is the superblock.
But then what?
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Debian grub bootloader / problem superblocks /UEFI
i have an Intel Nuc-8i3beh running a Debian 10 Buster and Windows 10 in dual boot. The Windows system was installed first. The bootloader is grub in uefi mode.
System:
sda -> main harddrive with ...
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mdadm not enough to start array - /dev/sdc2 no superblock
After a power failure on a server with 4 disks in RAID6 configuration, /dev/md1 won't come up (though /dev/md0 does).
mdadm --assemble --scan
mdadm: /dev/md/1 assembled from 3 drives - not enough to ...
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ext4 - Bad magic number in super-block
ext4 is failed me again! the most unstable fs
tried to fix it by restoring block from backup, but without luck..
↪ sudo fsck.ext4 -v /dev/sdd
e2fsck 1.45.6 (20-Mar-2020)
ext2fs_open2: Bad magic number ...
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What is the most efficient way to search a block device for valid (filesystem) superblocks?
I have a block device that contains some valid filesystem (including the main and backup superblocks) at some unknown offset with some unknown block size. In my case I happen to know that it's an ext4 ...
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How to fix if I received mount: /dev/vgname/lvname: can't read superblock for the local filesystem?
I received an incident when I was trying to do mount -a .
I was getting the below error. So how to fix this issue?
mount: /dev/vgname/lvname: can't read superblock
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All superblocks corrupt, mismatched start sector on extended and logical partitions
While running Linux Mint 19 Cinnamon normally, the drive went into lockdown mode preventing disk writes indicating possible corruption. Upon shutdown and reboot I was met with ACPI errors.
Following ...
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Why do my software RAID1 superblocks keep getting corrupted and how can I prevent this?
How might I be repeatedly corrupting my superblocks on RAID1
I have had two occasions in the past six months of RAID1 root arrays becoming unusable because of problems with the superblock. ...
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Ubuntu won't boot [duplicate]
My laptop ran out of power and when I went to plug it in and power it on, Ubuntu no longer boots. I get directed to BusyBox built in shell that looks exactly like:
BusyBox v1.27.2 (Ubuntu 1:1.27.2-...
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Bad magic number in super-block: dm-crypt device
I have a device that is encrypted using dm-crypt. This is a mini SD card that I use on my laptop.
I've had some issues with my laptop freezing recently, and in the journal these messages come up:
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Superblock replicas in ext4
I am trying to find the association between block groups and superblocks in an ext4 filesystem
I was unable to find much of documentation online, except this link that hints that
Because of the ...
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Manually backup superblock - how to & does it make sense?
Background
The first block of an ext4 filesystem is called the superblock - it contains essential metadata. There are backup copies of the superblock scattered throughout the filesystem; they can be ...
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