NB: I see this type of error message show up a lot in the GUI:
>> "Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8;"
>>> *************** Error ***************
Failed to execute command 'export PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin; export LANG=C.UTF-8; omv-installdocker docker install': Docker storage :: /var/lib/docker
Agent port:: 8000
Web port:: 9000
Yacht port:: 8001
arch :: amd64
option :: docker
state :: install
extras :: 5.4.2
DNS OK.
Create override file ...
Reload systemd daemon ...
Get:1 file:/var/cache/openmediavault/archives InRelease
Ign:1 file:/var/cache/openmediavault/archives InRelease
Get:2 file:/var/cache/openmediavault/archives Release
Ign:2 file:/var/cache/openmediavault/archives Release
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Ign:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Get:3 file:/var/cache/openmediavault/archives Packages
Get:4 file:/var/cache/openmediavault/archives Translation-en
Ign:4 file:/var/cache/openmediavault/archives Translation-en
Hit:5 http://deb.debian.org/debian buster InRelease
Hit:6 http://linux.teamviewer.com/deb stable InRelease
Hit:7 http://deb.debian.org/debian buster-updates InRelease
Hit:8 http://security.debian.org/debian-security buster/updates InRelease
Hit:9 https://openmediavault.github.io/packages usul InRelease
Hit:10 https://download.docker.com/linux/debian buster InRelease
Hit:11 http://httpredir.debian.org/debian buster-backports InRelease
Ign:12 https://dl.bintray.com/openmediavault-plugin-developers/usul buster InRelease
Ign:13 https://dl.bintray.com/openmed…in-developers/usul-extras buster InRelease
Get:14 https://dl.bintray.com/openmediavault-plugin-developers/usul buster Release [4363 B]
Get:15 https://dl.bintray.com/openmed…in-developers/usul-extras buster Release [3538 B]
Hit:16 http://packages.openmediavault.org/public usul InRelease
Fetched 7901 B in 1s (8774 B/s)
Reading package lists...
Failed to update apt repos.
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