[systemd-devel] Identical mount resulting in different options

[Florian Lindner]

Hello!

I am on an Arch Linux machine. Kernel is 3.9.3 x86_64, systemd 204.

I have two identical hard drives. Both have a gparted created GPT table and a 
CLI created ext4 filesystem with no options other than -L (label).
Archiv_1 was created like two weeks before Archiv_2 (which was created right 
now). I don't know about the exact kernel version or Archiv_1.

Both are set in fstab with identical fstab options:

LABEL=Archiv_1  /mnt/Archiv_1           ext4            defaults
LABEL=Archiv_2  /mnt/Archiv_2           ext4            defaults

yet they are actually mounted using a different option:

/dev/sde1 on /mnt/Archiv_1 type ext4 (rw,relatime)
/dev/sdd1 on /mnt/Archiv_2 type ext4 (rw,relatime,data=ordered)

Default mount options from tune2fs are identical:

root at horus /mnt/Archiv_2 # tune2fs -l /dev/sde1 | grep "mount options" 
Default mount options:    user_xattr acl
root at horus /mnt/Archiv_2 # tune2fs -l /dev/sdd1 | grep "mount options" 
Default mount options:    user_xattr acl

so is the mount file in run/systemd/generator/

But somehow systemd uses different options:

root at horus ~ # systemctl show mnt-Archiv_1.mount > A1
root at horus ~ # systemctl show mnt-Archiv_2.mount > A2
root at horus ~ # diff -y A1 A2
[...]
Where=/mnt/Archiv_1                                           | 
Where=/mnt/Archiv_2

What=/dev/sde1                                                | What=/dev/sdd1

Options=rw,relatime,rw                                        | 
Options=rw,relatime,rw,data=ordered
[...]


Why is that?

Thanks!

Florian