Where should I mount my internal drive partitions?
As far as I searched on the internet, I came to know that
/Media = mount point for removable media that system do it itself ( usb drive , CD )
/Mnt = temporarily mounting anything manually
I can most probably mount anything wherever I want, but if that’s the case what’s the point of /mnt? Just to be organised I suppose.
TLDR
If /mnt is for temporary and /media is for removable where should permanent non-removable devices/partitions be mounted. i.e. an internal HDD which is formatted as NTFS but needs to be automounted at startup?
Asking with the sole reason to know that, what’s the practice of user who know Linux well, unlike me.
I know this is a silly question but I asked anyway.
What does this do? I’m a Meganoob.
?
you mean the whole /mnt is meant to single mount point?
Sorry for all the questions.
chmodis the command to change user permissions. The numbers mean user, group, and others and the value allows read, write, execute. So, 000 means no one has permissions to get rid of the mount point. 777 means everyone has all permissions. (4 is read, 2 is write, and 1 is execute and the numbers are added. So, 644 would mean you can read/write, the group and other users have read only access.)You don’t have to use the numbers but eventually, almost every Linux admin does because it’s faster, a bit like a keyboard shortcut. But, for instance, you can add Execute permission with
chmod +x /some/file/location.Here’s more details on the how to chmod and the historic reasons for the 0-7 system (spoiler: it’s 8 bits): https://www.redhat.com/sysadmin/linux-file-permissions-explained
Thank You for the detailed answer.
chmod vs chwon ?
chownchanges the file owner.chmodchanges permissions. So, if a file or directory is owned by root but a user should have access, you could make them the owner or you could keep root the owner and just allow read/write access.They come up more on servers where you often have multiple users with different access levels. Some users might not have
sudopermission but do have full control over their home directory and whatever else they need. And web servers, for instance, will usually have a user calledwww-dataor similar and it’s shared by all the users in the “developer” group.Thanks.
Adding to what the other comment explained:
I use
chown 000so that regular users fail to access a directory when no filesystem is mounted on it; in practice it never happens, because “regular users” = { me }, but I like being pedantic.As for /mnt, it is supposed to be a single temp. mountpoint, but I use it as the parent directory of multiple mountpoints some of which are just for temporary use.
My dummy brain can’t understand it man.
Isn’t someone can’t access a directory when no filesystem is mounted on it the default behaviour?
No, directories without anything mounted on them are normal directories - which checks out, since you can mount anything anywhere; unlike Windows volume letters, which only exist when volumes are mounted or detected by the OS.
When you mount a filesystem onto a directory, the OS “replaces” its contents AND permissions with that of the filesystem’s root.
Here’s an example with my setup (hopefully you’re somewhat familiar with Bash and the output of
ls -l).Imagine some random filesystem in
/dev/sda1owned by “user” which only contains a file named “/Hello World.txt”:$ # List permissions of files in /mnt: $ # note that none of the directories have read, write nor execute permissions $ ls -la /mnt drwxr-xr-x 1 root root 168 May 31 23:13 . drwxr-xr-x 1 root root 128 May 31 23:14 .. d--------- 1 root root 0 Aug 1 2020 a/ d--------- 1 root root 0 Feb 11 2022 b/ d--------- 1 root root 0 Aug 11 2021 vdisks/ $ # No read permission on a directory => directory entries cannot be listed $ ls /mnt/a cannot open directory '/mnt/a': Permission denied $ sudo mount /dev/sda1 /mnt/a $ # List again the permissions in /mnt: the root of /dev/sda1 $ # has rwxr-xr-x (or 755) permissions, which override the 000 of /mnt/a ... $ ls -la /mnt drwxr-xr-x 1 root root 168 May 31 23:13 . drwxr-xr-x 1 root root 128 May 31 23:14 .. drwxr-xr-x 1 root root 0 Aug 1 2020 a/ d--------- 1 root root 0 Feb 11 2022 b/ d--------- 1 root root 0 Aug 11 2021 vdisks/ $ # ... and its contents can be accessed by the mounted filesystem's owner: $ ls -la /mnt/a drwxr-xr-x 1 user user 168 May 31 23:13 . drwxr-xr-x 1 root root 168 May 31 23:13 .. -rw-r--r-- 1 user user 0 Jul 4 22:13 'Hello World.txt' $ find /mnt /mnt /mnt/a /mnt/a/Hello World.txt find: ‘/mnt/b Permission denied find: ‘/mnt/vdisks’: Permission deniedPlease note that me setting permissions is just extreme pedantry, it’s not necessary at all and barely changes anything and if you’re still getting familiar with how the Linux VFS and its permissions work you can just ignore all of this.
So, the original content is lost forever?
So, what’s the actual use case of it though? Even though it’s pedantry, it still there has to be some benefits, right?
I mean, What’s the need for you to deny the access of
/mnt/auntill has mounted with something? One can just leave it as it is, right?No, but it becomes invisible and inaccessible* as long as the filesystem is mounted over it - see this Stack Exchange question and accepted answer.
The benefits are marginal, for example I can see if a filesystem is mounted by simply typing
ll /mnt(llbeing an alias ofls -lA) - it comes handy with my system due to how I manage a bunch of virtual machines and their virtual disks, and it’s short and easy to type.Some programs may refuse to write inside inaccessible directories, even if the root user can always modify regular files and directories as long as the filesystem supports it.
It’s not a matter of security, it’s more of a hint that if I’m trying to create something inside those directories then I’m doing something wrong (like forgetting to mount a filesystem) and “permission denied” errors let me know that I am.
Now I understand.
This is all new to me bro.
Even I don’t know if I will go this further to explain something to someone.
Thanks Chad.