Mounting disks in host computers

There are multiple ways of automating disk mounting. We will discuss disk mounting using the /etc/fstab file and a mountfs daemon service

fstab method

This is a /etc/fstab file

I added

# USB Mass storage device 
# /dev/disk/by-uuid/E4C75361C8523252   /media/WD_USB_HDD/  fuseblk  defaults  0  0
# this via `gnome-disks`
/dev/disk/by-uuid/E4C75361C8523252 /media/WD_USB_HD auto nosuid,nodev,nofail,x-gvfs-show 0 0

After adding

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/ubuntu-vg/ubuntu-lv during curtin installation
/dev/disk/by-id/dm-uuid-LVM-k5cgR1nZM1b2a4at1ht0fdf4glwuMvq3pQvqh0iVV1bGxU1fbrl7Z3mSyOwIMV5e / ext4 defaults 0 1
# /boot was on /dev/sda2 during curtin installation
/dev/disk/by-uuid/6981be89-9bab-4d00-8aad-118645013431 /boot ext4 defaults 0 1
# /boot/efi was on /dev/sda1 during curtin installation
/dev/disk/by-uuid/3A70-DE26 /boot/efi vfat defaults 0 1
/swap.img       none    swap    sw      0       0
# USB Mass storage device 
# /dev/disk/by-uuid/E4C75361C8523252   /media/WD_USB_HDD/  fuseblk  defaults  0  0


/dev/disk/by-uuid/E4C75361C8523252 /media/WD_USB_HD auto nosuid,nodev,nofail,x-gvfs-show 0 0

or use UUID=...

UUID=fd7766e7-96b5-49d6-9603-b63db21359b2 /mnt/SD_CARD_1 ext4           x-gvfs-show              0 0

sometimes you can just mount the path directory. Below is a case where I have just used the fdisk utility to

Delete existing partitions. (with option d)
Crerate a new GNU partitiaon table. (with option g)
Create a new partition. (option n )
Set partition type to linux (with option ‘t’)
write changes (with w)
then format the new partition to ext4
edit fastab to auto muountthe partition.

Note that I have used partiton 1

formatting the partition

sudo mkfs.ext4 /dev/nvme0n1p1

updates to fstab

/dev/nvme0n1p1 /mnt/ssd-disk/ ext4 defaults 0 0

checking if mounts work

ganindu@ubuntu:/mnt/SD_CARD_1$ sudo mount -av
/                        : ignored
/mnt/SD_CARD_1           : successfully mounted
ganindu@ubuntu:/mnt/SD_CARD_1$ sudo vim /etc/fstab 

Note: The directory (mount point) has to be present and empty

Afterwards you can use sudo mount -a to test these changes

Note:

you may ignore these errors

before reboot
[E] unreachable on boot required target: No such file or directory
after reboot
[E] cannot detect on-disk filesystem type

Alternative approach

usecase: Create a NTFS formatted USB drive for logging

when formattting give it a distinct name e.g. “SENSOR_DATA_LOGGING_USB”

Then tou will see the label on /dev/disk/by-label/PM_SENSOR_DATA_LOGGER

then add the following line to the fstab file!

 LABEL=PM_SENSOR_DATA_LOGGER /mnt/PM_LOGGING_USB/ auto nosuid,nodev,nofail,x-gvfs-show 0 0

directory permissions for other users

You can create a user group and give the group permission for a directory

create a group

sudo groupadd new.group

add users to the group

sudo usermod -aG sudo $USER

to check memebers in a group use getent e.g.

getent group adm

then change group of the directory

sudo usermod -aG new.group $NEW_USER
or
chown -R owners_username:crazy_user_group the_directory_to_give_permissions/
or
sudo chgrp -R new.group /path/to/the/directory

give correct permissions

sudo chmod -R g+rwx /path/to/the/directory

to make all new files and directories inherit the ownership and permissions

sudo find /path/to/the/directory -type d -exec chmod 2775 {} \;

to inherit read write access

sudo find /path/to/the/directory -type f -exec chmod ug+rwx {} \;

source

Service daemon method

Service Daemons are background processes that can be defined by the user and managed by the operating system. In this example our mount is a network share, our goal is to mount this as a file accessible as a mounted folder in a systm resource optimal way.

resource: 172.16.1.39:/DS/myshare
target: /mnt/my_share_mount

create a file named mnt-my_share_mount.mount in the /etc/systemd/system directory.

Note the naming of the file in respect to the directory (forward slashes convert to dashes)

[Unit]
Description=Mount NFS Share at boot

[Mount]
What=172.16.1.39:/DS/myshare
Where=/mnt/my_share_mount
Type=nfs
Options=defaults

[Install]
WantedBy=multi-user.target

Move the file to /etc/systemd/system with

sudo mv mnt-my_share_mount.mount /etc/systemd/system/

Reload the daemon

sudo systemctl daemon-reload

Enable and srart the service

sudo systemctl enable mnt-my_share_mount.mount
sudo systemctl start mnt-my_share_mount.mount

output of sudo systemctl enable mnt-my_share_mount.mount

Created symlink /etc/systemd/system/multi-user.target.wants/mnt-my_share_mount.mount → /etc/systemd/system/mnt-my_share_mount.mount.

Check status with sudo systemctl status mnt-qnap_ganindu.mount

you will see something simlilar as the response if everything went well

● mnt-qnap_ganindu.mount - Mount NFS Share at boot
     Loaded: loaded (/etc/systemd/system/mnt-my_share_mount.mount; enabled; vendor preset: enabled)
     Active: active (mounted) since Mon 2023-09-11 17:00:39 BST; 4s ago
      Where: /mnt/my_share_mount
       What: 172.16.1.39:/DS/myshare
      Tasks: 0 (limit: 618847)
     Memory: 140.0K
        CPU: 5ms
     CGroup: /system.slice/mnt-my_share_mount.mount

Sep 11 17:00:38 dgx systemd[1]: Mounting Mount NFS Share at boot...
Sep 11 17:00:39 dgx systemd[1]: Mounted Mount NFS Share at boot.

you can check it further with

df -h

or the mount command