Since version 3.0.99 is EOL I decided to go to version 4.
First, I uninstalled all OMV extras except flashmemory, then I did omv-update, which went through without errors except for the end:
"Err http://httpredir.debian.org jessie-backports/main amd64 Packages 404 Not Found
Err http://httpredir.debian.org jessie-backports/contrib amd64 Packages 404 Not Found
Err http://httpredir.debian.org jessie-backports/non-free amd64 Packages 404 Not Found
Fetched 21.8 MB in 17s (1234 kB/s)
W: Failed to fetch http://httpredir.debian.org/de…ain/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://httpredir.debian.org/de…rib/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://httpredir.debian.org/de…ree/binary-amd64/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable)
E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
That didn't seem to worry me, so I did an omv-release-upgrade. This also went without a hitch, except for the end:
"root@OMV:~# omv-release-upgrade
Upgrading system to 4.0 (Arrakis) ...
Ign file: InRelease
Ign file: Release.gpg
Ign file: Release
Ign http://debian.mirror.lrz.de stretch InRelease
Hit http://debian.mirror.lrz.de stretch-updates InRelease
Hit http://packages.openmediavault.org arrakis InRelease
Ign file: Translation-en
Ign file: Translation-de
Ign file: Translation-de_DE
Hit http://debian.mirror.lrz.de stretch Release.gpg
Hit http://debian.mirror.lrz.de stretch Release
Hit http://security.debian.org stretch/updates InRelease
Ign http://httpredir.debian.org jessie-backports InRelease
Get:1 http://debian.mirror.lrz.de stretch-updates/main Sources/DiffIndex [12.5 kB]
Get:2 http://debian.mirror.lrz.de stretch-updates/contrib Sources [32 B]
Get:3 http://debian.mirror.lrz.de stretch-updates/non-free Sources [32 B]
Get:4 http://debian.mirror.lrz.de stretch-updates/main amd64 Packages/DiffIndex [12.5 kB]
Get:5 http://debian.mirror.lrz.de stretch-updates/contrib amd64 Packages [32 B]
Get:6 http://debian.mirror.lrz.de stretch-updates/non-free amd64 Packages [32 B]
Ign http://httpredir.debian.org jessie-backports Release.gpg
Get:7 http://debian.mirror.lrz.de stretch-updates/contrib Translation-en [14 B]
Get:8 http://debian.mirror.lrz.de stretch-updates/main Translation-en/DiffIndex [6640 B]
Get:9 http://debian.mirror.lrz.de stretch-updates/non-free Translation-en [14 B]
Ign http://httpredir.debian.org jessie-backports Release
Hit http://packages.openmediavault.org arrakis/main amd64 Packages
Get:10 http://security.debian.org stretch/updates/main Sources [200 kB]
Get:11 http://security.debian.org stretch/updates/contrib Sources [1384 B]
Get:12 http://security.debian.org stretch/updates/non-free Sources [1216 B]
Get:13 http://security.debian.org stretch/updates/main amd64 Packages [508 kB]
Ign http://httpredir.debian.org jessie-backports/main amd64 Packages/DiffIndex
Get:14 http://security.debian.org stretch/updates/contrib amd64 Packages [1760 B]
Get:15 http://debian.mirror.lrz.de stretch/main Sources [6747 kB]
Get:16 http://security.debian.org stretch/updates/non-free amd64 Packages [1596 B]
Get:17 http://security.debian.org stretch/updates/contrib Translation-en [1759 B]
Ign http://packages.openmediavault.org arrakis/main Translation-en
Ign http://packages.openmediavault.org arrakis/main Translation-de
Get:18 http://security.debian.org stretch/updates/main Translation-en [224 kB]
Ign http://packages.openmediavault.org arrakis/main Translation-de_DE
Ign http://httpredir.debian.org jessie-backports/contrib amd64 Packages/DiffIndex
Get:19 http://security.debian.org stretch/updates/non-free Translation-en [691 B]
Ign http://httpredir.debian.org jessie-backports/non-free amd64 Packages/DiffIndex
Get:20 http://debian.mirror.lrz.de stretch/main amd64 Packages [7086 kB]
Get:21 http://debian.mirror.lrz.de stretch/main Translation-en [5385 kB]
Get:22 http://debian.mirror.lrz.de stretch/main Translation-de [1620 kB]
Get:23 http://debian.mirror.lrz.de stretch/main Translation-de_DE [830 B]
Ign http://httpredir.debian.org jessie-backports/contrib Translation-en
Ign http://httpredir.debian.org jessie-backports/contrib Translation-de
Ign http://httpredir.debian.org jessie-backports/contrib Translation-de_DE
Ign http://httpredir.debian.org jessie-backports/main Translation-en
Ign http://httpredir.debian.org jessie-backports/main Translation-de
Ign http://httpredir.debian.org jessie-backports/main Translation-de_DE
Ign http://httpredir.debian.org jessie-backports/non-free Translation-en
Ign http://httpredir.debian.org jessie-backports/non-free Translation-de
Ign http://httpredir.debian.org jessie-backports/non-free Translation-de_DE
Err http://httpredir.debian.org jessie-backports/main amd64 Packages 404 Not Found
Err http://httpredir.debian.org jessie-backports/contrib amd64 Packages 404 Not Found
Err http://httpredir.debian.org jessie-backports/non-free amd64 Packages 404 Not Found
Fetched 31.7 kB in 12s (2460 B/s)
W: Failed to fetch http://httpredir.debian.org/de…ain/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://httpredir.debian.org/de…rib/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://httpredir.debian.org/de…ree/binary-amd64/Packages 404 Not Found"
After that I still had version 3.0.99:
root@OMV:~# uname -a
Linux OMV 4.9.0-0.bpo.6-amd64 #1 SMP Debian 4.9.88-1+deb9u1~bpo8+1 (2018-05-13) x86_64 GNU/Linux
dpkg -l | grep openmediavault
root@OMV:~# dpkg -l | grep openmediavault
ii openmediavault 3.0.99 all Open network attached storage solution
ii openmediavault-flashmemory 3.5 all folder2ram plugin for OpenMediaVault
ii openmediavault-keyring 1.0 all GnuPG archive keys of the OpenMediaVault archive
What went wrong?
Hardware Terramaster F2-220 with Systemdrive Transcend SSD370S 32 GB SATA and Datadrive Western Digital WD Red 4TB RAID 1