Hello again, I've looked at the names of those symlinks and other remaining files in the "partial" directory, and found something hopefully leading to a solution.
The file names were all related to Debian "Jessie". The Pi-hole application I already mentioned, insisted (wrongfully) on the PHP version provided there, this is the reason why I kept it in the sources list. In particular, the following three lines cause the problem on my machine: ---8<------------------------------------- deb [ trusted=yes check-valid-until=no ] http://archive.debian.org/debian/ jessie main contrib non-free deb [ trusted=yes check-valid-until=no ] http://archive.debian.org/debian/ jessie-backports main contrib non-free deb [ trusted=yes check-valid-until=no ] http://archive.debian.org/debian/ jessie-backports-sloppy main contrib non-free ---8<------------------------------------- Commenting them out solves the problem, it occures again after re-activating those, and calling "apt(-get) update" afterwards. This does NOT happen with "Stretch" (tested here on the same machine), which is also archived. The aforementioned problems of pi-hole aren't the problems of Debian, of course; however, there are legitimate reasons for keeping something from such an old release around, and the bug will occur no matter whether another application misbehaves, so I think that should be fixed. "check-valid-until=no" "removes being an error" in Apt that "Jessie is too old", "trusted=yes" eliminates the error that all signing keys have expired. But then, this bug creates the symlinks leading to the error message when bzip2 tries to decompress actually uncompressed files. So "apt(-get) update" exits with a non-zero value, which routinely breaks scripts, despite of the problem being mostly harmless if you are updating/installing manually. The following are the "remainders" I've found in my "partial" directory whenever the above 3 lines are present in sources.list: ---8<------------------------------------- -rw-r--r-- 1 root root 148222 23. Jun 2018 archive.debian.org_debian_dists_jessie_Release -rw-r--r-- 1 root root 2420 23. Jun 2018 archive.debian.org_debian_dists_jessie_Release.gpg -rw-r--r-- 1 root root 9098100 16. Feb 2019 archive.debian.org_debian_dists_jessie_main_binary-amd64_Packages.gz -rw-r--r-- 1 root root 9100355 16. Feb 2019 archive.debian.org_debian_dists_jessie_main_binary-i386_Packages.gz lrwxrwxrwx 1 root root 83 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_binary-i386_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_binary-i386_Packages lrwxrwxrwx 1 root root 82 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_i18n_Translation-en.bz2 -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_i18n_Translation-en lrwxrwxrwx 1 root root 87 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_i18n_Translation-de%5fDE.bz2 -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_i18n_Translation-de%5fDE lrwxrwxrwx 1 root root 84 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_binary-amd64_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_binary-amd64_Packages lrwxrwxrwx 1 root root 82 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_i18n_Translation-de.bz2 -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_i18n_Translation-de lrwxrwxrwx 1 root root 80 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_Contents-i386.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_Contents-i386.lz4 lrwxrwxrwx 1 root root 81 6. Nov 03:59 archive.debian.org_debian_dists_jessie_main_Contents-amd64.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_main_Contents-amd64.lz4 lrwxrwxrwx 1 root root 86 6. Nov 03:59 archive.debian.org_debian_dists_jessie_contrib_binary-i386_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_contrib_binary-i386_Packages lrwxrwxrwx 1 root root 85 6. Nov 03:59 archive.debian.org_debian_dists_jessie_contrib_i18n_Translation-en.bz2 -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_contrib_i18n_Translation-en lrwxrwxrwx 1 root root 84 6. Nov 03:59 archive.debian.org_debian_dists_jessie_contrib_Contents-amd64.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_contrib_Contents-amd64.lz4 lrwxrwxrwx 1 root root 87 6. Nov 03:59 archive.debian.org_debian_dists_jessie_contrib_binary-amd64_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_contrib_binary-amd64_Packages lrwxrwxrwx 1 root root 83 6. Nov 03:59 archive.debian.org_debian_dists_jessie_contrib_Contents-i386.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_contrib_Contents-i386.lz4 lrwxrwxrwx 1 root root 87 6. Nov 03:59 archive.debian.org_debian_dists_jessie_non-free_binary-i386_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_non-free_binary-i386_Packages lrwxrwxrwx 1 root root 88 6. Nov 03:59 archive.debian.org_debian_dists_jessie_non-free_binary-amd64_Packages.xz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_non-free_binary-amd64_Packages lrwxrwxrwx 1 root root 86 6. Nov 03:59 archive.debian.org_debian_dists_jessie_non-free_i18n_Translation-en.bz2 -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_non-free_i18n_Translation-en lrwxrwxrwx 1 root root 84 6. Nov 03:59 archive.debian.org_debian_dists_jessie_non-free_Contents-i386.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_non-free_Contents-i386.lz4 lrwxrwxrwx 1 root root 85 6. Nov 03:59 archive.debian.org_debian_dists_jessie_non-free_Contents-amd64.gz -> /var/lib/apt/lists/archive.debian.org_debian_dists_jessie_non-free_Contents-amd64.lz4 ---8<------------------------------------- As you can see, ".xz" and ".bz2" extensions link to uncompressed files, while ".gz" extensions link to ".lz4" files. Because of "ls -lArt" the files above from Nov. 6th should be in creation order. The locale settings might also be important (look at the "… i18n … %5fDE …" line above): ---8<------------------------------------- LANG=de_DE.UTF-8 LANGUAGE= LC_CTYPE="de_DE.UTF-8" LC_NUMERIC="de_DE.UTF-8" LC_TIME="de_DE.UTF-8" LC_COLLATE="de_DE.UTF-8" LC_MONETARY="de_DE.UTF-8" LC_MESSAGES="de_DE.UTF-8" LC_PAPER="de_DE.UTF-8" LC_NAME="de_DE.UTF-8" LC_ADDRESS="de_DE.UTF-8" LC_TELEPHONE="de_DE.UTF-8" LC_MEASUREMENT="de_DE.UTF-8" LC_IDENTIFICATION="de_DE.UTF-8" LC_ALL= ---8<------------------------------------- Christoph Franzen
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