Fedora 15 - Gnome 3 - df output is odd

[Adunaic]

Hi,

I get the following output from df.

Filesystem            Size  Used Avail Use% Mounted on
rootfs                 20G   15G  4.7G  76% /
udev                  2.0G     0  2.0G   0% /dev
tmpfs                 2.0G  412K  2.0G   1% /dev/shm
tmpfs                 2.0G  800K  2.0G   1% /run
/dev/sda3              20G   15G  4.7G  76% /
tmpfs                 2.0G     0  2.0G   0% /sys/fs/cgroup
tmpfs                 2.0G     0  2.0G   0% /media
/dev/sda6             396G  4.0G  372G   2% /mnt/media
/dev/sda3              20G   15G  4.7G  76% /tmp
/dev/sda3              20G   15G  4.7G  76% /var/tmp
/dev/sda3              20G   15G  4.7G  76% /home

Which confuses me. I do not know what is going on. There seems to be a lot of duplication and I am confused about this.

The contents of /etc/fstab is:

UUID=8ce17071-2ef1-42c8-806b-6669a3eee431 /                       ext4    defaults        1 1
UUID=a813709b-8e01-4bd8-8d16-4e91ebcc9d6a /mnt/media              ext4    defaults        1 2
UUID=1fbf40e6-ed62-4f42-94b4-b76629b6410c 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

any explanation?

[bodhi.zazen]

The duplicate listings of /dev/sda3 is due to sandbox.

See : http://blog.bodhizazen.net/linux/selinux-sandbox/

https://bugzilla.redhat.com/show_bug.cgi?id=712093

I hope that is what you are asking about =)

[DBelton]

systemd creates some of those mounts for you, like /run, /sys/fs/cgroup, /media. Those are tmpfs filesystems that it uses.

udev created /dev which is where it defines all of your devices.

If you don't have a separate /home partition, then it mounts /home as a regular folder in your / partition. (same with /tmp and /var/tmp)

Edit:

He doesn't seem to be getting the weird duplicate mounts that sandbox causes, so I don't think he's running sandbox. those /dev/sda3 mounts are the standard mounts for /, /home, /tmp, and /var/tmp. They are all /dev/sda3 because separate partitions weren't created for them.

[Adunaic]

Thanks to you both. I am not conciously using sandbox (thus I do not think I am running it). I noticed in gparted it lists /dev/sda3 as being mounted to 4 mount points, / /home /tmp /var/tmp. Is this just a new way of doing things?

[DBelton]

well, F15 stuck the sandbox service in there on bootup for a lot of people without them knowing about it.

I think linux has always created the / and /home mount points if they are in the same partition and not specified in /etc/fstab, and I believe /tmp as well. I think /var/tmp was a result of the systemd change, but not certain. However, it's possible that this is all due to the systemd change as well. I have always created /home in a separate partition so I can't recall how it does for certain now.

[bodhi.zazen]

Originally Posted by Adunaic

Thanks to you both. I am not conciously using sandbox (thus I do not think I am running it). I noticed in gparted it lists /dev/sda3 as being mounted to 4 mount points, / /home /tmp /var/tmp. Is this just a new way of doing things?

As I said, those duplicates due to sandbox, which starts automatically.

If you wish, stop it and re-check

systemctl status sandbox.service

systemctl stop sandbox.service

If you wish you may disable sandbox, although I do not really see it as causing a problem, and you might want to try it before you disable it.

systemctl disable sandbox.service

[DBelton]

just checked here, and you're correct, bodhi.zazen.

I was thinking that sandbox created the /tmp and /var/tmp mounts as tmpfs if they weren't already mounted, but was wrong.

I also found out that just stopping sandbox would not change his df output. They remain mounted even after stopping sandbox. You would have to either unmount them, or disable sandbox and reboot to get rid of them.

[bodhi.zazen]

Originally Posted by DBelton

I also found out that just stopping sandbox would not change his df output. They remain mounted even after stopping sandbox. You would have to either unmount them, or disable sandbox and reboot to get rid of them.

Thank you for that, I seemed to recall sandbox automatically unmounted them when it was stopped, but obviously have not tried recently.

Will include that info next time (this is a FAQ).

[DBelton]

This is a FAQ

This is a FAQ on drugs..

This is a FAQ running F15 :moon:

[jpollard]

As a historical note - /var/tmp was created somewhere around 1985 when SunOS (then a BSD based system) was being reconfigured to allow diskless clients (what is now called "thin" clients). The root filesystem was a minimal filesystem (/etc, /lib, /sbin, and a very small /tmp) mounted over NFS. This root had the node specific configuration files. Once the root was booted, then /usr would be added - and this /usr was shared among all clients. To give reasonable log space, workspace, and other stuff - /var was mounted. /var/tmp was sometimes a symbolic link to /tmp, and /tmp was mounted. Each node had their own /var (and/or /tmp), but if /var/tmp was mounted, it sometimes was shared among all nodes. /home was also mounted, and usually shared among all, though when automounts were added, this did not exactly apply as only the users home directory was mounted on login, and others would be mounted (sometimes) when referenced.

[edwinexil]

Is it known why sandbox services cause the duplicate issue?

[jpollard]

Yes. There are several threads on that such as:

http://forums.fedoraforum.org/archiv.../t-269319.html.

A general search of the forums for "disable sandbox" will show a lot more.

I believe the "why" is that each sandbox is implemented using bind mounts to reduce file duplication (ie for chroot sandboxes) and minimize the complexity of system updates not reaching everywhere a file needs to be updated. Easily a problem when multiple sandboxes are established.