What on earth is mounted?

[Phil Meyer]

On 05/25/2011 12:17 PM, Tom Horsley wrote:
> I was checking to see if I had everything mounted that I wanted
> in a newly genned f15 system, and I see this insanity in
> the output from running "mount":
>
> /dev/sda2 on / type ext3 (rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=ordered)
> /dev/sda2 on /tmp type ext3 (rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=ordered)
> /dev/sda2 on /var/tmp type ext3 (rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=ordered)
> /dev/sda2 on /home type ext3 (rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=ordered)
>
> Where on earth do those /tmp /var/tmp and /home entries come from?
> They certainly aren't all mounted on top of the same filesystem root.
> There are no entries for them in /etc/fstab. What is going on?
>
> They also all show up with identical free space entries in the
> output from the df command.
>
> This is just wayyyy confusing.
>
> Can I make it stop somehow and leave them as ordinary subdirectories
> as they have always been?

Hha!  That's nothing.  I raise you.

Here is my fstab:

# cat /etc/fstab

#
# /etc/fstab
# Created by anaconda on Thu Mar 10 01:14:06 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=f73ffe10-516a-47a5-b139-d52f36b1d58e /                       
ext4    defaults        1 1
UUID=cd1e4fc9-26cb-463f-973f-067490589686 /boot                   
ext4    defaults        1 2
UUID=33d692f2-f40f-4121-844a-8fbd74aced41 /home                   
btrfs   defaults        1 2
UUID=9866462a-0124-49d8-a8d2-0f2248a683ab 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


Here is the output of mount:

# mount
/proc on /proc type proc (rw,relatime)
/sys on /sys type sysfs (rw,relatime)
udev on /dev type devtmpfs 
(rw,nosuid,relatime,size=4082156k,nr_inodes=1020539,mode=755)
devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /dev/shm type tmpfs (rw,relatime)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,mode=755)
/dev/sda3 on / type ext4 (rw,relatime,barrier=1,data=ordered)
tmpfs on /sys/fs/cgroup type tmpfs 
(rw,nosuid,nodev,noexec,relatime,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup 
(rw,nosuid,nodev,noexec,relatime,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
cgroup on /sys/fs/cgroup/ns type cgroup (rw,nosuid,nodev,noexec,relatime,ns)
cgroup on /sys/fs/cgroup/cpu type cgroup 
(rw,nosuid,nodev,noexec,relatime,cpu)
cgroup on /sys/fs/cgroup/blkio type cgroup 
(rw,nosuid,nodev,noexec,relatime,blkio)
systemd-1 on /dev/mqueue type autofs 
(rw,relatime,fd=29,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs 
(rw,relatime,fd=30,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /dev/hugepages type autofs 
(rw,relatime,fd=31,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /sys/kernel/security type autofs 
(rw,relatime,fd=32,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
systemd-1 on /sys/kernel/debug type autofs 
(rw,relatime,fd=34,pgrp=1,timeout=300,minproto=5,maxproto=5,direct)
tmpfs on /media type tmpfs (rw,nosuid,nodev,noexec,relatime,mode=755)
tmpfs on /var/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,mode=755)
tmpfs on /var/run type tmpfs (rw,nosuid,nodev,noexec,relatime,mode=755)
/dev/sda1 on /boot type ext4 (rw,relatime,barrier=1,data=ordered)
/dev/sdb1 on /home type btrfs (rw,relatime)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
/dev/sda3 on /tmp type ext4 (rw,relatime,barrier=1,data=ordered)
/dev/sda3 on /var/tmp type ext4 (rw,relatime,barrier=1,data=ordered)
/dev/sdb1 on /home type btrfs (rw,relatime)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)
mqueue on /dev/mqueue type mqueue (rw,relatime)
securityfs on /sys/kernel/security type securityfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
cgroup on /sys/fs/cgroup/cpuset type cgroup 
(rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/cpuacct type cgroup 
(rw,nosuid,nodev,noexec,relatime,cpuacct)
cgroup on /sys/fs/cgroup/memory type cgroup 
(rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/devices type cgroup 
(rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/freezer type cgroup 
(rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/net_cls type cgroup 
(rw,nosuid,nodev,noexec,relatime,net_cls)