MDADM damaged?

[solderdot]

Dear community,
I'm facing a strange issue with mdadm. I intend creating a RAID5 on 4 pendrives, which worked perfectly fine in the past. I use an image which is based on BusterLite plus SSH being enabled and a fixed IP address being configured, all this in a headless setup. To create the RAID array I do the following:

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sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install mdadm
sudo blkid
sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1

With sudo blkid I check that the pendrives actually reside on sda1 to sdd1, which is the case.
The mdadm --create leads to an error message:

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modprobe: ERROR: ../libkmod/libkmod.c:586 kmod_search_moddep() could not open moddep file '/lib/modules/4.19.66-v7l+/modules.dep.bin'
modprobe: FATAL: Module md_mod not found in directory /lib/modules/4.19.66-v7l+

Indeed, the directory /lib/modules/4.19.66-v7l+ does not exist. Instead I see 4.19.75+. Apparently something newer is installed on my Raspi, bvut for some reason mdadam intends using an older version.
This is 100% reproducible on my system.
Here is the full output of mdadm --create:

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pi@raspberrypi:~ $ sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1
mdadm: layout defaults to left-symmetric
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 512K
mdadm: partition table exists on /dev/sda1
mdadm: partition table exists on /dev/sda1 but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdb1
mdadm: partition table exists on /dev/sdb1 but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdc1
mdadm: partition table exists on /dev/sdc1 but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdd1
mdadm: partition table exists on /dev/sdd1 but will be lost or
       meaningless after creating array
mdadm: size set to 30700544K
Continue creating array? y
modprobe: ERROR: ../libkmod/libkmod.c:586 kmod_search_moddep() could not open moddep file '/lib/modules/4.19.66-v7l+/modules.dep.bin'
modprobe: FATAL: Module md_mod not found in directory /lib/modules/4.19.66-v7l+
mdadm: Fail create md0 when using /sys/module/md_mod/parameters/new_array
mdadm: unexpected failure opening /dev/md0

Any ideas what might cause that phenomenon and how to overcome this?

[jj_0]

Did you reboot after the dist-upgrade? If a new kernel is installed it won't be active until after reboot. After that it should look for modules in the 4.19.75+ modules directory.

[solderdot]

Urgs! Yes, I missed that.
I guess, now this thread should be moved to the "Beginners" forum.
Sorry for having bothered you, but many thanks for bringing me back on track in virtually no time.
Best regards