Syncthing won't install

I run a newly installed freedombox over a newly installed debian bullseye, over rpi 4b.
clicked the Syncthing install button on plinth.

I get this error:

Error installing app: (‘Apt command failed with return code: 100’, b’Setting up php7.4-json (7.4.33-1+deb11u3) …\nSetting up linux-image-5.10.0-21-arm64 (5.10.162-1) …\nSetting up php7.4-opcache (7.4.33-1+deb11u3) …\nSetting up php7.4-cli (7.4.33-1+deb11u3) …\nSetting up php7.4-fpm (7.4.33-1+deb11u3) …\nProcessing triggers for initramfs-tools (0.140) …\nupdate-initramfs: Generating /boot/initrd.img-5.10.0-10-arm64\nProcessing triggers for php7.4-cli (7.4.33-1+deb11u3) …\nProcessing triggers for php7.4-fpm (7.4.33-1+deb11u3) …\nfreedombox set on hold.\n’, b’\x1b[97m INFO\x1b[0m \x1b[94mplinth.app \x1b[0m Initialized apps - apache, api, names, avahi, storage, backups, cockpit, firewall, config, datetime, diagnostics, dynamicdns, first_boot, help, letsencrypt, networks, power, security, snapshot, ssh, sso, upgrades, users, privacy, bepasty, bind, calibre, coturn, deluge, ejabberd, gitweb, i2p, ikiwiki, infinoted, jsxc, matrixsynapse, mediawiki, minetest, minidlna, mumble, openvpn, pagekite, performance, privoxy, quassel, radicale, roundcube, samba, searx, shaarli, shadowsocks, sharing, syncthing, tor, transmission, ttrss, wireguard, wordpress, zoph, email, janus, rssbridge\ndebconf: unable to initialize frontend: Dialog\ndebconf: (Dialog frontend will not work on a dumb terminal, an emacs shell buffer, or without a controlling terminal.)\ndebconf: falling back to frontend: Readline\ndebconf: unable to initialize frontend: Readline\ndebconf: (This frontend requires a controlling tty.)\ndebconf: falling back to frontend: Teletype\n/etc/kernel/postinst.d/initramfs-tools:\nupdate-initramfs: Generating /boot/initrd.img-5.10.0-21-arm64\ncp: error reading '/sbin/blkid': Input/output error\nE: /usr/share/initramfs-tools/hooks/udev failed with return 1.\nupdate-initramfs: failed for /boot/initrd.img-5.10.0-21-arm64 with 1.\nrun-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1\ndpkg: error processing package linux-image-5.10.0-21-arm64 (–configure):\n installed linux-image-5.10.0-21-arm64 package post-installation script subprocess returned error exit status 1\ndebconf: unable to initialize frontend: Dialog\ndebconf: (Dialog frontend will not work on a dumb terminal, an emacs shell buffer, or without a controlling terminal.)\ndebconf: falling back to frontend: Readline\ndebconf: unable to initialize frontend: Readline\ndebconf: (This frontend requires a controlling tty.)\ndebconf: falling back to frontend: Teletype\ndpkg: dependency problems prevent configuration of linux-image-arm64:\n linux-image-arm64 depends on linux-image-5.10.0-21-arm64 (= 5.10.162-1); however:\n Package linux-image-5.10.0-21-arm64 is not configured yet.\n\ndpkg: error processing package linux-image-arm64 (–configure):\n dependency problems - leaving unconfigured\ndebconf: unable to initialize frontend: Dialog\ndebconf: (Dialog frontend will not work on a dumb terminal, an emacs shell buffer, or without a controlling terminal.)\ndebconf: falling back to frontend: Readline\ndebconf: unable to initialize frontend: Readline\ndebconf: (This frontend requires a controlling tty.)\ndebconf: falling back to frontend: Teletype\ndebconf: unable to initialize frontend: Dialog\ndebconf: (Dialog frontend will not work on a dumb terminal, an emacs shell buffer, or without a controlling terminal.)\ndebconf: falling back to frontend: Readline\ndebconf: unable to initialize frontend: Readline\ndebconf: (This frontend requires a controlling tty.)\ndebconf: falling back to frontend: Teletype\nNOTICE: Not enabling PHP 7.4 FPM by default.\nNOTICE: To enable PHP 7.4 FPM in Apache2 do:\nNOTICE: a2enmod proxy_fcgi setenvif\nNOTICE: a2enconf php7.4-fpm\nNOTICE: You are seeing this message because you have apache2 package installed.\ncp: error reading '/sbin/blkid': Input/output error\nE: /usr/share/initramfs-tools/hooks/udev failed with return 1.\nupdate-initramfs: failed for /boot/initrd.img-5.10.0-10-arm64 with 1.\ndpkg: error processing package initramfs-tools (–configure):\n installed initramfs-tools package post-installation script subprocess returned error exit status 1\nNOTICE: Not enabling PHP 7.4 FPM by default.\nNOTICE: To enable PHP 7.4 FPM in Apache2 do:\nNOTICE: a2enmod proxy_fcgi setenvif\nNOTICE: a2enconf php7.4-fpm\nNOTICE: You are seeing this message because you have apache2 package installed.\nErrors were encountered while processing:\n linux-image-5.10.0-21-arm64\n linux-image-arm64\n initramfs-tools\nquota not working (qgroup not set)\nConfig is in use.\nE: Sub-process /usr/bin/dpkg returned an error code (1)\nquota not working (qgroup not set)\nquota not working (qgroup not set)\nE: Sub-process /usr/bin/dpkg returned an error code (1)\n\x1b[31m ERROR\x1b[0m \x1b[94m__main__ \x1b[0m Error executing action: Apt command failed with return code: 100\nTraceback (most recent call last):\n File “/usr/share/plinth/actions/actions”, line 92, in _call\n return_values = func(*arguments['args'], **arguments['kwargs'])\n File “/usr/lib/python3/dist-packages/plinth/privileged/packages.py”, line 69, in install\n raise RuntimeError(\nRuntimeError: Apt command failed with return code: 100\n’)

How could I fix it?

It is not just installing Syncthing, it is also trying to update packages including the Linux kernel. And it is failing here.

Can you check if there is sufficient free disk space? The command df -h will show this for each filesystem.

df -h

Filesystem Size Used Avail Use% Mounted on
udev 875M 0 875M 0% /dev
tmpfs 185M 20M 165M 11% /run
/dev/sda2 224G 5.9G 217G 3% /
tmpfs 923M 0 923M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
/dev/sda2 224G 5.9G 217G 3% /.snapshots
tmpfs 185M 0 185M 0% /run/user/10000

It is a fairly new install. installation process:
downloaded the image for my rpi 4b, installed as documented. created an admin user, configured DMZ and a ddns.
than tried to install Syncthing, nothing more than that.
it shows quite the same error when I try to install any other app.

update from the Cockpit app solved it. thanks!