Q4OS Forum

Steve

Member

Registered: 2015-12-07

Posts: 14

Support for Q4OS on Raspberry Pi 2

Over the last 72 hours I have been trying to mount partition mmcblk0p3 such that user 'pi' has read-write access to that partition.  Despite multiple experiments I have failed.

No matter what I do, no matter how I create the partition or which option I use to mount the partition it is always 'root' who is owner of the partition.  User 'pi' has no access.  During this process I have made multiple new, clean installations of Q4OS to make sure my unsuccessful experiments have done no damage.

I will describe my final experiment:  I wrote the Q4OS image onto a 32Gb micro-SD card and booted up.  I logged in as user 'pi'.  User 'pi' then installed gparted and used gparted to create partition /dev/mmcblk0p3.  User 'pi' opened My Computer -> System Media and used the mount option to mount  /dev/mmcblk0p3.  The partition was successfully mounted and via View -> Detailed list I was able to see that 'root' was owner of the partition which user 'pi' had created and mounted.  Via Krusader I was able to see that the mount point for mmcblk0p3 that the system had automatically created was /media/<uuid>.

At this point, perhaps I should explain why I choose this configuration for RPi/RPi2 systems.  I separate user data into a separate partition so that I can take backup images of the operating system partitions.  Then, when a system crash does occur, I can roll in the latest backup (without the need to rebuild the system from scratch and without the restore process having any effect on the user data in the mmcblk0p3 partition).  It also allows the cloning of successfull systems onto multiple micro-SD cards for multiple RPi2 systems (each with their own user data).

I have now used multipe methodologies where user 'pi' creates and mounts mmcblk0p3 successfully but always with the same result: pi is not the owner of the partition and has no access.

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 4,501

Website

Re: Support for Q4OS on Raspberry Pi 2

Real disk partitions should always be created and owned by root, as GParted properly did. You could mount that partition as user, if you will add 'user' option to fstab related line, for example:
/dev/mmcblk0p2  /mnt/mntpoint  ext4  defaults,noatime,user  0  2

Depending on filesystem type you may need to properly set ownership and permissions of the mounted filesystem to gain user write access:
$ sudo chown -R pi:pi /mnt/mntpoint
check ownership and permissions:
$ ls -l /mnt/mntpoint

If you want to learn something about fstab options, we recommend nice article here http://pclosmag.com/html/issues/200709/page07.html

Steve

Member

Registered: 2015-12-07

Posts: 14

Re: Support for Q4OS on Raspberry Pi 2

During my experiments I did read a couple of articles on fstab usage and added a line to fstab (including the 'user' option) that I believe should have worked.  Unfortunately it did not.  Thank you for the link. An extra explanation is welcome.

I will give it another go in a few days time.  In the short term there are other things I must do.

At a logical level, what I am trying to do is the equivelent of moving the /home folder into a separate partition.  That is normally a very simple operation, even on Debian systems.  The option is simply specified during the system install process.

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 4,501

Website

Re: Support for Q4OS on Raspberry Pi 2

It's possible to migrate your 'home' to another partition, you don't need to mount partitions as a user. In general, you need to move all files in '/home' to the new partition and add record to fstab. Detailed procedure you will find here https://www.maketecheasier.com/move-home-folder-ubuntu/

We recommend you to follow this procedure, excluding GParted part, and let findings here, we will try to assist on any issues.

Steve

Member

Registered: 2015-12-07

Posts: 14

Re: Support for Q4OS on Raspberry Pi 2

q4osteam, thank you for your help.  I do now have mmcblk0p3 mounted and user 'pi' has read-write access to the partition.

Once I resumed my experiments, I had a couple more failed attempts.  Lines added to fstab that should have worked did not work.  So I decided to abandon ext formatting.  I reformatted mmcblk0p3 as ntfs.  The move to a fuse file system allowed me to add three additional ntfs specific options to fstab, uid, gid and utf8.  I used the same standard options as before.

That worked.  It seems that no matter what you put in fstab, if the file system is ext, user 'pi' will not get write access.  But once the uid and gid of the intended user have been explicitly stated, that user is awarded write access.

For the moment I've added a script to the /home folder to mount my data partition.  Five mouse clicks and it's done.  If I discover how to create desktop icons, perhaps I will be able to reduce five single mouse clicks to one double-click.

As I noted above, the rationale for having user data in a separate partition is to facilitate making backup images of the q4os system partitions.  To do this successfully you must leave 4Mb of unallocated space between the end of the q4os root partition and the start of the user added partition(s).  The q4os-1.4.4-rpi image installs two partitions on the micro-SD card.  The boot partition (mmcblk0p1) and the root partition (mmcblk0p2).  Together they occupy the first 4125Mb of the micro-SD card.  So the number of 4Mb blocks you need to export (via the dd command) to make a backup is 1032.

I noticed that when q4os is running, user 'pi' has read-only access to the boot partition.  That partition includes config.txt.  However the user has legitimate reasons to want to (and need to) edit config.txt.  Of course it can be done off-line.  But I would rather see a self-contained system than one which obliges users to edit the q4os partitions off-line.  That means, as a minimum, read-write access to config.txt via a text editor.

I also saw that the boot partition has the bcm2708 dtb files.  I've not tried running q4os on a original RPi (though I will, just for the hell of it), but since the system is not designed to run on the original RPi, I'm wondering why those files have been included.

I made one attempt at moving the /home folder to a separate partition.  It's quite a tricky business.  Not the sort of thing ordinary users should be encouraged to try.

Now that I undersatnd how to separate my data from my operating system, I'm going to have fun with q4os!

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 4,501

Website

Re: Support for Q4OS on Raspberry Pi 2

user 'pi' has read-only access to the boot partition

All files in '/boot' are system files properly owned by root. You have to have root permissions to work with that files, for example use 'sudo' command to edit config.txt:
$ sudo nano /boot/config.txt

If I discover how to create desktop icons, perhaps I will be able to reduce five single mouse clicks to one double-click.

Simply drag&drop icons from menu to desktop or by right mouse click on desktop and 'Create new ...'

It seems that no matter what you put in fstab, if the file system is ext, user 'pi' will not get write access.

Ext3/4 filesystem works fine, we were not able to reproduce as you described. You need to create ext3 partition, mount it, move '/home' dir to that partition, optionally set ownership on files and dirs, and finally add mount record to 'fstab' or '/etc/rc.local'.

Steve

Member

Registered: 2015-12-07

Posts: 14

Re: Support for Q4OS on Raspberry Pi 2

I've been searching Q4OS (without success) to try and find a reference to a firewall. 

So now the question:  Is there a built-in firewall in Q4OS for RPi2?

If yes, how do I list/change firewall settings?

If no, do you have a recommended/preferred firewall for users to install?

... by the way, I was using ext2 before switching to ntfs.

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 4,501

Website

Re: Support for Q4OS on Raspberry Pi 2

'gufw' is simple, easily configurable and user friendly GUI firewall frontend. You can install 'gufw' using Synaptic or command-line:
$ sudo apt-get install gufw

'ufw' is command-line based firewall https://wiki.debian.org/Uncomplicated%2 … ll%20(ufw) , also very easily configurable, we would recommend this solution.

If you want to have full control over firewall rules, you should build them using iptables https://wiki.debian.org/iptables

Steve

Member

Registered: 2015-12-07

Posts: 14

Re: Support for Q4OS on Raspberry Pi 2

I recently played around with an experimental build of a linux version for RPi2 which had a copy of Xine media player installed.  Xine was able to use hardware acceleration on RPi2.  A web search and a visit to the VLC forum brought me the follwing information:  VLC can also use hardware acceleration on RPI2, apparently it's all finished and the VLC people are waiting for Debian/Raspbian to package it.  In the meantime various people have made their own builds of VLC for RPi2 with hardware acceleration enabled.  Something to do with compiling with a -omxil switch.