setting up a drive automount in systemd?

[dep <dep@drippingwithirony.com>]

greetings.

i've tried my best to search the list archives for the answer to this and have not gotten the search function to deliver . . . anything.

here's the issue. i have one of the new "gemini" devices, a psion-like smartphone-pda-computer that runs android and linux. i'm of course running linux. the linux available for it is a derivative of stretch arm64. it uses systemd, my first encounter with that not-universally-loved arrangement.

the device has 64gb of onboard storage and a microSD slot, in which i've placed a 128gb microSD card formatted ext4. to reduce write wear on the device's internal memory, it's my hope to put /home or at least /[users] on the microSD card. this of course requires mounting it at boot.

i've been much of a week searching and i cannot find any way to configure this to automount in systemd. i do not even know if under systemd it must be mounted to a mountpoint or if it's handled at the /dev level. so what was once a trivial configuration has become a more complicated one, with the possibility of bricking the device -- which i'd just as soon not do.

can anyone here either give or point to clear and i hope simple instructions for configuring the card to mount at boot? alternately, is there systemd-friendly disk management software? the disk managers i'm familiar with do not seem to work with systemd.

thanks in advance.

dep

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