home mounted twice?

[vasco]

Hi,

I just started using Fedora because I am picking the Gnome 3 side in the Unity vs Gnome 3 thing. I am not sure if I will stick with Fedora, but it looks very good thus far.

On topic:
I was looking at the output of the mount command, here is a snippet:

...
/dev/sda1 on / type ext4 (rw,noatime,seclabel,barrier=1,data=ordered)
/dev/sda3 on /home type ext4 (rw,noatime,seclabel,barrier=1,data=ordered)
/dev/sda1 on /tmp type ext4 (rw,noatime,seclabel,barrier=1,data=ordered)
/dev/sda1 on /var/tmp type ext4 (rw,noatime,seclabel,barrier=1,data=ordered)
/dev/sda3 on /home type ext4 (rw,noatime,seclabel,barrier=1,data=ordered)
...

It seems like /home is mounted twice. Secondly, how come sda1 is mounted on /, /tmp, /var/tmp, I am not used to the output of mount looking like this.

Can anybody explain whats going on?

[PatMcLJr]

how about a
# cat /etc/fstab

look the same?

Pat Jr.

[vasco]

$ cat /etc/fstab 
#
# /etc/fstab
# Created by anaconda on Wed May 18 18:30:36 2011
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
UUID=939b4209-142e-42b0-953e-abe3fab170bd /                   ext4    defaults,noatime        1 1
UUID=ac3ce7ca-6fd7-4466-8392-51630e5c2cab /home               ext4    defaults,noatime        1 2
UUID=5ce55992-95fa-4fa3-a78d-7d99a15a90d4 swap                swap    defaults        0 0
tmpfs                   /dev/shm                tmpfs   defaults        0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0

[jpollard]

You are seeing a bind mount done for you.

Why it is done I don't know.

[vasco]

Is it normal in Fedora 15?

[jpollard]

I think it happens way more than it should. Duplicates such as yours shouldn't exist, but currently doesn't hurt anything as the overlayed mount goes to the same location.

Bind mounts were created to permit easier BSD style chroot jails without having to duplicate files for libraries and jailed utilities. They are an implementation adapted from Plan 9 to support name spaces that can be used to lock logins without as much overhead as traditional chroot jails have.

Using them the way F15 is doing it seems overkill and silly.

[JEO]

The output of the mount command uses the /etc/mtab file and it can be wrong. Check the output of "cat /proc/mounts" to see if it is duplicated there or not.

[jpollard]

Fedora 15 has chosen to make /etc/mtab a symbolic link to /proc/mounts.

There is no longer any difference.