On 10/31/2015 08:28 AM, Richard Owlett wrote:
I'm having problems understanding
http://manpages.debian.org/cgi-bin/man.cgi?query=mount&apropos=0&sektion=0&manpath=Debian+6.0.10+squeeze&format=html&locale=en
I have 3 partitions labeled proj-all, proj-1, and proj-2.
The machine intentionally has no networking.
There are 2 relevant but minimally privileged users [u1 and u2].
I wish to have proj-all mounted at power on with read/write/execute
privileges for both u1 and u2.
proj-1 and/or proj-2 will be mounted separately if required.
Once mounted, u1 and u2 will each have read/write access.
How do I accomplish this.
I don't use labels much in Linux, but they can be helpful when I have
multiple disk drives of the same make and model with identical
partitioning schemes.
I use UUID's to identify partitions in /etc/fstab. For example:
# /boot was on /dev/sda1 during installation
UUID=2ef32b38-2ede-491d-9d4d-e9da3282170f /boot
ext4 defaults,discard 0 2
"mount" connects a disk partition containing a file system into the
Linux file system heirarchical tree.
Traditional read, write, and execute permissions are controlled by the
"mode" bits:
https://en.wikipedia.org/wiki/Modes_%28Unix%29
So:
1. If you want all users to have full access to the file system on the
partition labeled "proj-all", then you need to create an empty directory
(mount point), mount the partition file system into that directory, and
set the "other" read, write, and execute mode bits of the directory once
mounted.
2. If you want just u1 and u2 to have full access to "proj-all", then
you need to create an empty directory, mount the partition, create a
group containing u1 and u2, change the group ownership of the directory
to the group you created, set the "group" read, write, and execute bits,
and clear the "other" bits.
3. If you want just u1 to have full access to "proj-1", then you need
to create an empty directory, mount the partition, and either create a
group with just u1 and do the above, or change the user ownership of the
directory to u1, set the "user" read, write, and execute bits, and clear
the "group" and "other" bits.
David
