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Questions tagged [umount]

46 questions
28
votes
7 answers

Lazy umount or Unmounting a busy disk in Linux

I have read that it is possible to 'umount' a disk that is otherwise busy by using the 'lazy' option. The manpage has this to say about it: umount - unmount file systems -l Lazy unmount. Detach the filesystem from the filesystem hierarchy now,…
deed02392
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18
votes
4 answers

How to really force unmount a filesystem (without manual investigation why is it busy)

How to unmount a filesystem in Linux without investigating why is it busy? I want to do it in one command. It should handle applications using that filesystem, submounts, containers (lxc-execute -n qqq ) and all other things. Just "unmount.…
Vi.
  • 17,755
17
votes
1 answer

Why is "sudo unmount" required for unmounting an sshfs-mount if it was mounted without sudo privilges?

I have an sshfs FUSE filesystem mounted in ~/mountpoint. I tried umount mountpoint and diskutil unmount mountpoint (on a Mac here) and both failed. I used sshfs -o IdentityFile= user@hostname:/home/ ~/mountpoint; none of that required…
Kyle L
  • 2,379
14
votes
1 answer

How to stop jbd2 to release a device

In an AWS EC2 instance, we have multiple EBS volumes. When I try to detach any of them, the umount command works, but the device can't be detached. # grep -c xvdj /proc/mounts 0 However, lsof reports that jbd2 is using the device. # lsof | grep…
Ayose
  • 141
9
votes
2 answers

With "umount", should I unmount the device path or mount point?

Is there a more-correct way to unmount a device/filesystem/etc? Should I umount the device I originally mounted or the mount point? mount /dev/sda1 /mnt/myusbstick do stuff umount /mnt/myusbstick OR umount /dev/sda1
tarabyte
  • 2,585
7
votes
3 answers

Why Linux /etc/fstab UUIDs are case sensitive?

I recently added a line for a USB memory stick to /etc/fstab, to be able to mount it automatically, using UUID to identify the device. Before I already have several external ext4 drives that have their UUIDs written in lowercase hexadecimal chars…
nrz
  • 183
7
votes
3 answers

How to umount / ? It's busy

I'm trying to use zerofree, which seems to be the answer for this: How to reduce VM size? I have successfully umounted /dev/sda1, and zerofree worked fine, releasing ~37gb. But I can't seem to umount or remount as read only /dev/mapper/mypc-root, it…
HappyDeveloper
  • 1,713
5
votes
1 answer

How do I umount device that has been mounted twice

I have a /dev/sdf mounted to /mnt/db and accidentally mounted it again to /mnt/db2 (I intended to mount /dev/sdh). Is there any way to umount /dev/sdf but only for the 2nd mount? The /mnt/db contains live databases, so I'd rather not have have…
Paul
5
votes
1 answer

mount and umount behaving differently when run under cron

Running CentOS 6 in AWS, and what I'm seeing is baffling me. There is an s3fs mount in /etc/fstab that sometimes loses its ability to read and write from. I have a cron job that worked great for months, that would simply test that the mount was good…
Joshua Grigonis
  • 321
4
votes
3 answers

What exactly happens when you "mount" a drive?

What underlying things happen when you mount a drive. Even when a drive isn't mounted, it is visible to the computer (such as sudo fdisk -l / diskutil -list). When a drive is mounted, is all that is happening is that the OS is giving a path to the…
agz
  • 8,438
3
votes
1 answer

Using dd command fails after the first mount

I am using dd command to copy disk drive /dev/sda on /dev/sdb. What I do is the following: I run dd if=/dev/sda of=/dev/sdb then mount /dev/sdb1 (note that /dev/sdb1 is not mounted on boot) to make sure that everything is there. This works…
nikozavar
  • 31
3
votes
1 answer

Partition went read-only, how to mount it again?

Every now and then the partition of my Linux installation goes read-only. Since the computer is a laptop, I suppose it's due to some writing error caused by some harsh movement. Partition was mounted as: UUID=34h3k4hdf ... / ext4 …
Quora Feans
  • 688
3
votes
3 answers

why can't I umount /home?

I'm trying to create a new partition on my Linux system, my intent is to take a small amount of my /home filesystem and change the type for experimentation. I'm using OpenSuse 12.1 in a virtual box. gparted shows I have the following…
Mike
  • 1,069
2
votes
2 answers

Unmount unnecessary drives

My disk position looks like this: # df -HP Filesystem Size Used Avail Use% Mounted on /dev/sda2 256G 177G 67G 73% / /dev/sda1 510M 18M 467M 4% /boot tmpfs 8.5G 0 8.5G 0%…
shantanuo
  • 2,883
2
votes
1 answer

/var, /var/log on separate partition fails to umount on shutdown, how to debug

As the title says, I have /var and /var/log on separate partitions. On shutdown, I get the error, that umount /var/log, and later umount /var failed. My question is: How to debug this issue? If it counts, I am running Debian Stretch. So far I was…
Zoltan K.
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