Installscript for OMV on RaspberryPi (with Raspian 9 lite) install:
cd /tmp
sudo bash omv-rpi-install.sh
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After installation & reboot you have to access your OMV thru a browser http://x.x.x.x User: admin Password: openmediavault
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Beware: The installation will disable ssh for user pi. You have to reactivate it thru the OMV webfrontend: Acces Rights Management -> Users -> Edit -> Groups -> tick the ssh box! Save -> Apply -> Yes
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If you installed OMV-Extras: Disable backport Repos: System -> OMV-Extras -> Backports -> tick the red button Disable Backports
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sources:
https://openmediavault.readthedocs.io/en/latest/installation/on_debian.html
https://forum.openmediavault.org/index.php/Thread/5549-OMV-Extras-org-Plugin/
https://forum.armbian.com/topic/9044-openmediavault-from-softys-omv-keyring/