DietPi-Drive_Manager | Hotplug mount+fstab using udev rules

[chips023]

echo 'ACTION=="add", KERNEL=="sd[a-z]", RUN+="/DietPi/dietpi/dietpi-drive_manager 3"' > /etc/udev/rules.d/99-dietpi-auto_mount.rules udevadm control --reload-rules or reboot

[MichaIng]

@hifitime As mentioned in the other issue, this feature has not yet been implemented. Drive manager exits with failure when executing with argument 3. But what could actually work is:

G_DEBUG=1 /DietPi/dietpi/dietpi-drive_manager

This runs the drive detection loop but then prints information about all detected drives only and exits. But the fstab creation/update is done within the loop, AFAIK.

[chips023]

OK, I get it..

in addition，I added rules to /etc/udev/rules.d/， which also didn't work...It looks like the rules are right..

nano /etc/udev/rules.d/media_by_label_auto_mount

KERNEL!="sd[a-z][0-9]", GOTO="media_by_label_auto_mount_end"
IMPORT{program}="/sbin/blkid -o udev -p %N"
ENV{ID_FS_LABEL}!="", ENV{dir_name}="%E{ID_FS_LABEL}"
ENV{ID_FS_LABEL}=="", ENV{dir_name}="usbhd-%k"
ACTION=="add", ENV{mount_options}="relatime"
ACTION=="add", ENV{ID_FS_TYPE}=="vfat|ntfs", ENV{mount_options}="$env{mount_options},utf8,gid=100,umask=002"
ACTION=="add", RUN+="/bin/mkdir -p /media/%E{dir_name}", RUN+="/bin/mount -o $env{mount_options} /dev/%k /media/%E{dir_name}"
ACTION=="remove", ENV{dir_name}!="", RUN+="/bin/umount -l /media/%E{dir_name}", RUN+="/bin/rmdir /media/%E{dir_name}"
LABEL="media_by_label_auto_mount_end"

[MichaIng]

@hifitime Looks a bid complicated but should work. Did you run udevadm control -R or rebooted to enable the new rules?

[chips023]

udevadm control --reload-rules or reboot Have tried, but still can't run, can't see any mount..

[MichaIng]

@hifitime Does dmesg or journalctl -r show some related logs when you plug and/or unplug a drive? In case increase the udev log level.

udevadm control --log-priority=info

Or to actively print to console

udevadm monitor

Ahh there is even a test command to simulate a certain event and print debug log:

udevadm test -a add /dev/sda1

[Joulinar]

@hifitime glad that the problem could be solved. Would it be possible to share the steps you have taken to get it solved? It might be other are interested in it as well 😉

[chips023]

I'm so happy too early... The problem is still there...

root@DietPi:~# udevadm test -a add /dev/sda1 This program is for debugging only, it does not run any program specified by a RUN key. It may show incorrect results, because some values may be different, or not available at a simulation run.

Load module index Skipping empty file: /etc/systemd/network/99-default.link Created link configuration context. Reading rules file: /etc/udev/rules.d/10-wifi-disable-powermanagement.rules Reading rules file: /etc/udev/rules.d/11-automount.rules Reading rules file: /lib/udev/rules.d/50-firmware.rules Reading rules file: /lib/udev/rules.d/50-udev-default.rules Reading rules file: /lib/udev/rules.d/55-dm.rules Reading rules file: /lib/udev/rules.d/60-block.rules Reading rules file: /lib/udev/rules.d/60-cdrom_id.rules Reading rules file: /lib/udev/rules.d/60-drm.rules Reading rules file: /lib/udev/rules.d/60-evdev.rules Reading rules file: /lib/udev/rules.d/60-input-id.rules Reading rules file: /lib/udev/rules.d/60-persistent-alsa.rules Reading rules file: /lib/udev/rules.d/60-persistent-input.rules Reading rules file: /lib/udev/rules.d/60-persistent-storage-dm.rules Reading rules file: /lib/udev/rules.d/60-persistent-storage-tape.rules Reading rules file: /lib/udev/rules.d/60-persistent-storage.rules Reading rules file: /lib/udev/rules.d/60-persistent-v4l.rules Reading rules file: /lib/udev/rules.d/60-sensor.rules Reading rules file: /lib/udev/rules.d/60-serial.rules Reading rules file: /lib/udev/rules.d/60-sunxi-tools.rules Reading rules file: /lib/udev/rules.d/64-btrfs.rules Reading rules file: /lib/udev/rules.d/70-joystick.rules Reading rules file: /lib/udev/rules.d/70-mouse.rules Reading rules file: /lib/udev/rules.d/70-power-switch.rules Reading rules file: /lib/udev/rules.d/70-touchpad.rules Reading rules file: /lib/udev/rules.d/70-uaccess.rules Reading rules file: /lib/udev/rules.d/71-axp-power-button.rules Reading rules file: /lib/udev/rules.d/71-seat.rules Reading rules file: /lib/udev/rules.d/73-seat-late.rules Reading rules file: /lib/udev/rules.d/73-special-net-names.rules Reading rules file: /lib/udev/rules.d/73-usb-net-by-mac.rules Reading rules file: /lib/udev/rules.d/75-net-description.rules Reading rules file: /lib/udev/rules.d/75-probe_mtd.rules Reading rules file: /lib/udev/rules.d/78-sound-card.rules Reading rules file: /lib/udev/rules.d/80-debian-compat.rules Reading rules file: /lib/udev/rules.d/80-drivers.rules Reading rules file: /lib/udev/rules.d/80-ifupdown.rules Reading rules file: /lib/udev/rules.d/80-net-setup-link.rules Reading rules file: /lib/udev/rules.d/85-hdparm.rules Reading rules file: /lib/udev/rules.d/85-hwclock.rules Reading rules file: /lib/udev/rules.d/89-alsa-ucm.rules Reading rules file: /lib/udev/rules.d/90-alsa-restore.rules Reading rules file: /lib/udev/rules.d/90-console-setup.rules Reading rules file: /lib/udev/rules.d/95-dm-notify.rules Reading rules file: /lib/udev/rules.d/99-systemd.rules Rules contain 24576 bytes tokens (2048 * 12 bytes), 13443 bytes strings 1848 strings (23487 bytes), 1210 de-duplicated (10683 bytes), 639 trie nodes used Failed to open device '/sys/dev/sda1': No such device Unload module index Unloaded link configuration context. root@DietPi:~# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 1 7.2G 0 disk └─sda1 8:1 1 7.2G 0 part mtdblock0 31:0 0 1.5M 0 disk mtdblock1 31:1 0 64K 0 disk mtdblock2 31:2 0 2.4M 0 disk mmcblk0 179:0 0 3.7G 0 disk └─mmcblk0p1 179:1 0 3.7G 0 part mmcblk0boot0 179:8 0 2M 1 disk mmcblk0boot1 179:16 0 2M 1 disk mmcblk1 179:24 0 29.7G 0 disk └─mmcblk1p1 179:25 0 3G 0 part /

[MichaIng]

@hifitime The output shows that there is at least no syntax issue with the udev rule. But the path was not given correctly, so no rules are applied. Please try:

udevadm test -a add $(udevadm info -q path -n /dev/sda1)

[MichaIng]

@hifitime Btw one main issue we'd need to think about is conflict between the udev rule and fstab entries on boot:

• If the drive is plugged on boot, ACTION=="add" will happen and mount the drive/execute drive manager, regardless of already existing fstab entry.
• Also for most external drives, this mount attempt will fail since the system is not yet ready for mounts when udev trigger happens (very early boot stage).
• So basically we must enable the udev rule AFTER boot has fully finished and disable it again on shutdown.
• Since we can never assume a successful shutdown, easiest is to place a symbolic link to a tmpfs like /tmp/dietpi-automount.rules and copy the actual rules file there as last boot step. So whenever the system looses power, on next boot the in-place udev rule will be an empty symlink once boot has finished.

For reference: https://dietpi.com/phpbb/viewtopic.php?t=5106

Would be also interesting how other hotplug mount implementations handle this. Actually "hotplug" is the better wording here to not mix up with regular "automount" on boot, like mixed up in above linked forum thread.