How to unmount "/home" from external hard disk

[premchand21]

Hello gurus,
I installed a new external hard drive as I wanted to mount the new hard drive to "/var/www" folder. But unfortunately I mounted to "/home" by mistake while testing something. I am banging my head to unmount the new hard drive from "/home" but it is not allowing me to do so. I also tried logging in as root and tried to unmont but I had no success.
I really appreciate if somebody could help me unmount "/home" from my the newly installed hard drive.

FYI: The main hard drive is mounted to "/" folder and the newly installed hard disk is installed to "/home" directory.

Thanks in advance!!!

[sanderd17]

Use a live CD.

How did you mount to /home? by editing the fstab file?

[premchand21]

Use a live CD.

How did you mount to /home? by editing the fstab file?

I mounted it by using "mount /dev/sdb2 /home"
I did not change anything in fstab file.

[sanderd17]

I mounted it by using "mount /dev/sdb2 /home"
I did not change anything in fstab file.

If you reboot it should be ok.

[premchand21]

If you reboot it should be ok.
I already rebooted it couple of times and the new hard drive is mounted to "/home" by default after the reboot. :(

[sanderd17]

can you give the output of the following commands?


mount
cat /etc/fstab
cat /etc/mtab


(please put them between CODE tags)

[premchand21]

# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
# / was on /dev/sda1 during installation
UUID=c40cdc31-3637-4861-8e12-917b74e146be / ext4 errors=remount-ro 0 1
# /home was on /dev/sda2 during installation
UUID=0f340538-43f2-40b6-991b-967aced850ed /home ext4 defaults 0 2
# swap was on /dev/sda3 during installation
UUID=792982d5-0d91-4aca-ac40-4501b2cbddc4 none swap sw 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec,utf8 0 0
/dev/sda1 /mnt/data1 ext3 defaults 0 2
/dev/sda2 /mnt/data2 ext3 defaults 0 2
/dev/sdb2 /mnt/webtools ext3 defaults 0 0
//mvfil002/groups6/WRTools /mnt/wrttools smbfs auto,credentials=/root/.credentials,uid=1000,umask=000,user 0 0




cat /etc/mtab
/dev/sdb1 / ext4 rw,errors=remount-ro 0 0
proc /proc proc rw 0 0
none /sys sysfs rw,noexec,nosuid,nodev 0 0
none /sys/fs/fuse/connections fusectl rw 0 0
none /sys/kernel/debug debugfs rw 0 0
none /sys/kernel/security securityfs rw 0 0
udev /dev tmpfs rw,mode=0755 0 0
none /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0
none /dev/shm tmpfs rw,nosuid,nodev 0 0
none /var/run tmpfs rw,nosuid,mode=0755 0 0
none /var/lock tmpfs rw,noexec,nosuid,nodev 0 0
none /lib/init/rw tmpfs rw,nosuid,mode=0755 0 0
/dev/sdb2 /home ext4 rw 0 0
/dev/sda1 /mnt/data1 ext3 rw 0 0
/dev/sda2 /mnt/data2 ext3 rw 0 0
binfmt_misc /proc/sys/fs/binfmt_misc binfmt_misc rw,noexec,nosuid,nodev 0 0

[sanderd17]

# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
# / was on /dev/sda1 during installation
UUID=c40cdc31-3637-4861-8e12-917b74e146be / ext4 errors=remount-ro 0 1
# /home was on /dev/sda2 during installation
UUID=0f340538-43f2-40b6-991b-967aced850ed /home ext4 defaults 0 2
# swap was on /dev/sda3 during installation
UUID=792982d5-0d91-4aca-ac40-4501b2cbddc4 none swap sw 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec,utf8 0 0
/dev/sda1 /mnt/data1 ext3 defaults 0 2
/dev/sda2 /mnt/data2 ext3 defaults 0 2
/dev/sdb2 /mnt/webtools ext3 defaults 0 0
//mvfil002/groups6/WRTools /mnt/wrttools smbfs auto,credentials=/root/.credentials,uid=1000,umask=000,user 0 0




cat /etc/mtab
/dev/sdb1 / ext4 rw,errors=remount-ro 0 0
proc /proc proc rw 0 0
none /sys sysfs rw,noexec,nosuid,nodev 0 0
none /sys/fs/fuse/connections fusectl rw 0 0
none /sys/kernel/debug debugfs rw 0 0
none /sys/kernel/security securityfs rw 0 0
udev /dev tmpfs rw,mode=0755 0 0
none /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0
none /dev/shm tmpfs rw,nosuid,nodev 0 0
none /var/run tmpfs rw,nosuid,mode=0755 0 0
none /var/lock tmpfs rw,noexec,nosuid,nodev 0 0
none /lib/init/rw tmpfs rw,nosuid,mode=0755 0 0
/dev/sdb2 /home ext4 rw 0 0
/dev/sda1 /mnt/data1 ext3 rw 0 0
/dev/sda2 /mnt/data2 ext3 rw 0 0
binfmt_misc /proc/sys/fs/binfmt_misc binfmt_misc rw,noexec,nosuid,nodev 0 0


you forgot the output of the command "mount" (I need this too). But anyway, there are some weird things here. Summary of your files:



# / was on /dev/sda1 during installation
and
/dev/sda1 /mnt/data1 ext3 defaults 0 2

# /home was on /dev/sda2 during installation
and
/dev/sda2 /mnt/data2 ext3 defaults 0 2

/dev/sdb2 /mnt/webtools ext3 defaults 0 0
and
/dev/sdb2 /home ext4 rw 0 0


What partition do you want to have where?

[premchand21]

Ohh here is the output for mount

mount
/dev/sdb1 on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw)
none on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type tmpfs (rw,mode=0755)
none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
none on /dev/shm type tmpfs (rw,nosuid,nodev)
none on /var/run type tmpfs (rw,nosuid,mode=0755)
none on /var/lock type tmpfs (rw,noexec,nosuid,nodev)
none on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
/dev/sdb2 on /home type ext4 (rw)
/dev/sda1 on /mnt/data1 type ext3 (rw)
/dev/sda2 on /mnt/data2 type ext3 (rw)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev)


Here is the output for df just in case

Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdb1 24027628 21780516 1026576 96% /
udev 1676736 316 1676420 1% /dev
none 1676736 1196 1675540 1% /dev/shm
none 1676736 148 1676588 1% /var/run
none 1676736 0 1676736 0% /var/lock
none 1676736 0 1676736 0% /lib/init/rw
/dev/sdb2 96124936 36505628 54736352 41% /home
/dev/sda1 480618344 14591324 441612960 4% /mnt/data1
/dev/sda2 961529388 16216192 896470332 2% /mnt/data2


I want sdb2 (which is the new hard drive) to point to /var/www

Thanks

[sanderd17]

I get the problem. In you fstab file, it says:



# / was on /dev/sda1 during installation
UUID=c40cdc31-3637-4861-8e12-917b74e146be / ext4 errors=remount-ro 0


And that doesn't get overwritten anywhere, and still mtab says your root directory is /dev/sdb1, and not sda1. Since you can't change partition numbers without problems, that means you have switched disks. So sda has become sdb. The UUID stays the same, but the order of a and b have changed.

That also means that this line


# /home was on /dev/sda2 during installation
UUID=0f340538-43f2-40b6-991b-967aced850ed /home ext4 defaults 0 2

says that sdb2 is mounted to /home.

Now, before you go any further, are you sure you want to unmount sdb2 from /home? Since it has been that way since you installed it.

I think you want sda2 mounted to /home.


Try booting up a live CD and see what partition you want where (draw a schema on a sheet of paper). See which files are on what partition.

[premchand21]

Yes I want to unmount sdb2 from /home as my purpose of installing a new hard drive is to mount it to /var/www

I am not aware of live CD :(
Could you please help to unmount it with some command in terminal

[sanderd17]

Yes I want to unmount sdb2 from /home as my purpose of installing a new hard drive is to mount it to /var/www

I am not aware of live CD :(
Could you please help to unmount it with some command in terminal

sdb is your old hard drive. You switched the order of the hard drives.

So you probably want sda2 mounted to your /home directory.

Now, if you want to do that, remove the lines



/dev/sda2 /mnt/data2 ext3 defaults 0 2
/dev/sdb2 /mnt/webtools ext3 defaults 0 0


from your fstab file, and mount sda2 as /var/www (after you moved everything from /var/www to that partition).

[fdrake]

from what i understand it looks like you have 2 partitions (/dev/sda2 and /dev/sdb2) mounted both in the same mount point (/home)

if you do sudo umount /home you will unmount your user account too so it will give you some error messages like device is busy. try instead this:



sudo umount /dev/sdb2
sudo mount /dev/sdb2 /mnt/webtools


if it shows any errors copy and paste here.