1

I want to set up an Lubuntu-Kiosk read-only. So I want everything that user does, written in the RAM only. When the Raspberry is restarted, everything is deleted.

I have tried using the package overlayroot: 

apt install overlayroot
nano /etc/overlayroot.conf

#--> overlayroot = "tmpfs"**
#REBOOT

But it didn't work.

I have got Lubuntu from: Ubuntu Pi flavour maker

Update: Content of /etc/overlayroot.conf

# This is the overlayroot config file
# ... nothing changed ...
#    which is a tmpfs in memory.
overlayroot_cfgdisk="disabled"
overlayroot="tmpfs"

Update 2

I also tried to regenerate initramfs (after change as proposed in Felix' link to Odroid forum: sudo update-initramfs -c -k $(uname -r)), nothing changed.

Also, lsmod does not show overlayfs module to be loaded.

Tr33Bug
  • 11
  • 3
  • I haven't played with LVM on the RPi, but *if* you can get LVM running, you might be able to [pull this off with snapshots](https://askubuntu.com/a/896404/606758). If LVM won't work, one of the other answers on that page may accomplish what you need. – b_laoshi Apr 26 '17 at 07:07
  • @b_laoshi Sounds like a viable option, but with LVM you would still do writes against the disk wouldnt you? You wouldnt increase the lifetime e.g.bof the SD-card. – Felix Apr 26 '17 at 07:55
  • @Felix is right. Writes against the SD card could reduce life expectancy of the SD card, although if that's a huge concern, /boot could be put on the SD card and / could be moved to external USB storage (likely with a performance hit). Given the small amount of RAM in the RPis, you almost have to assume any solution that creates a temp fs in RAM is going to end up writing to SWAP, so you're going to be writing against a disk anyway. – b_laoshi Apr 26 '17 at 08:45
  • Could you please edit your question and add the contents of `/etc/overlayroot.conf`? – b_laoshi Apr 27 '17 at 01:38
  • I had the same problem with the Odroid hardware (https://forum.odroid.com/viewtopic.php?t=24078), I guess it has something to do with `mkinitramfs` - I never fully understood what happens, though. – Felix Apr 28 '17 at 15:43
  • @G-ötz, given what you're trying to do, have you considered just setting it up to [use a guest account by default](https://askubuntu.com/questions/95405/how-to-enable-guest-account-automatic-login)? The [guest account can be customized](https://help.ubuntu.com/community/CustomizeGuestSession) if necessary, and anything done in guest gets destroyed on logout. I just put lubuntu on a card and am trying it out in my pi3. – b_laoshi May 05 '17 at 06:16
  • 1
    Okay, here's probably the issue... Even on lubuntu for RPi3, the mount device for `/` is specified in the kernel command line options found in the `/boot/cmdline.txt` file. All of the sudden, it's clear to me why this wouldn't work. The boot process for a Raspberry Pi is a bit different from what you see on your PC. I'm guessing it is these very differences that would make it impossible (?) for overlayroot to do its thing. – b_laoshi May 05 '17 at 06:48

0 Answers0