ShareOS

ShareOS is a free, open source alternative firmware for the D-Link DNS-320L, DNS-320 (rev A/B) and DNS-325 (later perhaps more, e.g. the DNS-327L).

It is a fork of Alt-F by João Cardoso. All credit for the original design, the hardware support and years of work goes to the Alt-F project — see LICENSE and COPYING for the GPLv2 terms.

Built by an AI. Apart from importing Alt-F, ShareOS was developed by Claude (Anthropic): architecture, all code, builds, tests and docs. Jan started the project, made the decisions and tested on the real box. Timeline with timestamps and screenshots: docs/DEVELOPMENT.md (Deutsch).

Testing and installing: docs/TESTING.md (Deutsch). First sign-in: http://<box-IP>/, user root, password shareos – the box asks you to set your own password right away (also for SSH). Translating the web interface: docs/TRANSLATING.md.

Status: public test versions (beta)

DNS-320L: the main device, tested on hardware with every release. More models from 0.2.0-beta.3: DNS-320 rev B, DNS-325 rev A, DNS-320 rev A – built; the DNS-325 rev A1 boots from flash (from 0.2.0-beta.9) and its buttons work (from 0.2.0-beta.10), the DNS-320 rev A/B are not tested yet; testers wanted: docs/DEVICES.md.

ShareOS runs from flash on the DNS-320L (kernel, initramfs and the system in UBI with a persistent overlay for settings and packages). Test releases (v0.2.0-beta.x, before that v0.1.0-beta.x; pre-releases, for test devices only) are published on GitHub Releases; a running ShareOS updates itself from there.

ShareOS is built on a current, maintainable base while keeping what made Alt-F easy to use: the stock U-Boot and the stock flash layout.

Install – from Alt-F or the D-Link firmware

No serial console, no soldering; the data on the disks is not touched. Details and troubleshooting: docs/SWITCHING.md (Deutsch).

1. From the latest release download the two files with your model's name (DNS-320L: DNS-320L-rev-Ax; other models: docs/DEVICES.md): ShareOS-<version>-<model>.bin and ShareOS-<version>-<model>.sysupgrade.tar.
2. Keep the .bin of your current firmware (e.g. Alt-F) for the way back.
3. Copy the .sysupgrade.tar to a USB stick (FAT32, exFAT or ext4) and plug it into the box. Without a stick the box downloads it from GitHub (network cable, DHCP).
4. Flash the ShareOS .bin on the firmware page of Alt-F or of the D-Link interface. Do not cut the power.
5. The box restarts and installs the system from the stick (orange USB LED blinks fast, a few minutes), then restarts once more into ShareOS.
6. Open http://<box-IP>/ (or http://<device-name>.local/), sign in as root / shareos and follow the setup wizard; add your disks under Storage – the data stays.

Updates afterwards: System → Firmware (from GitHub, or the .sysupgrade.tar as a file).

Back to Alt-F (or the D-Link firmware)

1. In ShareOS: System → Firmware → Install firmware file → choose the Alt-F .bin → Install. ShareOS checks the file (format, checksums, device) and reads it back after writing.
2. Restart: Alt-F starts, at the same IP address.
3. Flash the same Alt-F .bin once more on Alt-F's firmware page to get its add-on packages back.
4. To the D-Link firmware: from Alt-F, as with Alt-F itself (docs/SWITCHING.md).

If ShareOS does not start, U-Boot starts the D-Link rescue system ("mini firmware"), from which Alt-F can be flashed.

Features

Version in brackets = first release with the feature.

Storage

• Setup wizard: one disk, two separate disks, a mirror (RAID 1), RAID 0 or JBOD (mdadm; RAID 0/JBOD from beta.9), optional swap partition per disk
• Take over disks with data from Alt-F or the D-Link firmware as they are, nothing erased (Speicher → Laufwerke → übernehmen, 0.2.0-beta.17)
• File system per volume: ext4 (recommended: owners, storage limit per user, personal folders, apps), Btrfs, exFAT, NTFS (beta.7), ext3, ext2, FAT32 (beta.9)
• Share rights are also set as POSIX ACLs on the share folders (ext4, Btrfs), so every program of a user is held to them, not only SMB (0.2.0-beta.6)
• Snapshots: dated states of shares, personal folders or whole drives on another drive (hourly to weekly, hard links like rsnapshot, keep the last N plus days/weeks/months), restore with the file browser (0.2.0-beta.6)
• SMART values and health, disk standby, RAID status with sync progress, repair a mirror with a new disk (beta.9), mount/unmount/remove volumes
• Disk health page: rating with reasons, SSD life left, all SMART attributes, short/long self-tests by hand or by schedule (0.2.0-beta.12)
• USB sticks and disks: mounted at /mnt/usb-<name> when plugged in (FAT32, exFAT, NTFS, ext4, Btrfs), Safely remove, Format with exFAT, FAT32, NTFS or ext4 (beta.7)

Shares, users, files

• USB printers in the network: current printers without a driver (IPP over USB: AirPrint, Mopria, Windows), scanning over the network (eSCL), older printers over port 9100 (system app "printer", 0.2.0-beta.18)
• UPS over USB: charge and runtime, messages on a power failure, clean shutdown on battery (low battery, a percentage or minutes), other computers over the network (system app "nut", 0.2.0-beta.18)
• SMB 2/3 (ksmbd) and NFS v4 shares with read/write permissions per user and group, guest access optional; the crypto engine of the SoC computes the SMB 3 signatures (about three times as fast, 0.2.0-beta.17); compatibility mode up to SMB 2.1 for difficult clients (0.2.0-beta.17)
• Users and groups; one account for shares, web interface and apps; storage limit per user (ext4); import of Alt-F users with their passwords
• "My ShareOS": users with web access manage their own password, look, shares, storage, cloud and Paperless
• File browser in the web interface: admins for all drives and USB drives, users for their personal folder and the shares they have rights to (enabled per user; read-only shares stay read-only, also for apps); upload/download with progress, drag and drop, large files; trash per folder with restore and automatic emptying (0.2.0-beta.12)

Apps and integrations

• APPS area with a store from ShareOS-Apps – 38 web apps for files and office, media, network, security, development and everyday life: one-click install/update with SHA-256 check, own .sapp packages, more catalogs, visibility per user/group; apps run on their own port (8081/8444) (beta.6)
• App permissions: scheduled tasks (cron) as a restricted app user, schedule editable in the interface (beta.7)
• Open files from the file browser in apps (e.g. Webpad), save back; app SDK and ShareOS look for apps (/_shareos/theme.css, /_shareos/app.js), apps inside the interface (permission embed) (beta.9)
• App permission files: apps work with the folders of the box with the user's rights – ShareCommander (two-pane file manager), Webpad saves on the box; music and videos stream with seeking (beta.11)
• System apps: native programs for the terminal from the store – nano, htop (0.2.0-beta.1); strace, iperf3 (0.2.0-beta.2); bash (0.2.0-beta.5); store in sections with search (0.2.0-beta.5)
• Feature lock 0.2.0-beta.2: faster interface (results kept between requests, store refresh in the background), smaller system without OpenSSL, GIO and unused tools
• App data per account in the browser, file dialog of the box for apps (WinWeb Player plays music from the box) (0.2.0-beta.1)
• Cloud sync with rclone (Nextcloud/WebDAV, S3, SFTP, Google Drive …) for the device and per user, with schedule and bandwidth limit (beta.4)
• Paperless-ngx: inbox folders per user or shared (e.g. for a scanner), upload through the Paperless API (beta.4)
• Installable as an app (PWA), status address for widget apps (beta.4)
• "Share with" on Android: the installed app saves shared photos, files and links into Geteilt in the personal folder (0.2.0-beta.11)
• Remote access with Tailscale (system app tailscaled, starts by itself, admins only, permission tailscale for apps): the box in a tailnet without port forwarding, also behind DS-Lite (0.2.0-beta.7)
• Monitoring with Zabbix (system app zabbix-agent): the classic C agent in active mode, a few MB of memory, no open port, encrypted with PSK; SMART of every disk, RAID state, box temperature and fan as items with a Zabbix template – see docs/MONITORING.md (0.2.0-beta.15)
• Download automation with autobrr (system app, one for the box, admins only, permission autobrr for apps): IRC announces and RSS feeds, matching torrents go to the Transmission of a chosen account (0.2.0-beta.9)
• Apps keep their data on the box also for accounts without file access: a private folder per app and account (0.2.0-beta.9)
• Admins get a personal folder for apps too (their home, for root home/root on the apps drive), so app data no longer lands at the top of a drive (0.2.0-beta.10)
• App permissions sysinfo, netcheck, docker and tuya (admins only): SysMon, HomePing, DockerDeck and TuyaPulse show real data – the box's values, checks from the box, Docker hosts of the homelab, Tuya devices locally without the cloud (0.2.0-beta.11)
• App permission notify: apps send messages through the box's notifications (web interface, e-mail, push) – from their scheduled tasks with shareos-app-notify, from the browser with ShareOS.notify (admins); at most 20 an hour per app (0.2.0-beta.12)
• File dialog of the apps with the personal folder and the user's shares, also for accounts without file access (0.2.0-beta.11)
• System apps declare their service in app.json ("service"), ShareOS starts and stops it through the firmware's controller; how to submit a system app: sysapps/README.md (0.2.0-beta.9)
• Large system apps on the apps drive (link in /opt), the flash stays free (0.2.0-beta.7)
• Media server (DLNA/UPnP AV, MiniDLNA as a system app): TVs and players play music, videos and pictures from chosen shares (0.2.0-beta.6)
• VPN for the box in both directions (OpenVPN as a system app, app NetTunnel, admins only): as client with cleaned profiles, as server with its own CA and a ready-made profile per device; status chips of services and apps in the header (0.2.0-beta.6)
• Transmission with own torrents per user: system app transmission-daemon, app permission torrent; apps bring the system apps they need ("requires") (0.2.0-beta.4)
• Media jobs: FFmpeg as a system app, app permission media – convert audio, change the container of videos, cut, in the background with the user's rights (MediaTranscoder) (0.2.0-beta.5)

Firmware and system

• Online updates from GitHub Releases: checked every 6 hours, SHA-256 verified, progress for download, check and installation (beta.1)
• First installation from the Alt-F or D-Link web interface: the .bin fetches the system from a USB stick or from GitHub (beta.7; tested on real hardware, step by step: SWITCHING.md · UMSTIEG.md)
• Back to Alt-F (or any D-Link .bin) from the firmware page, checked and read back (beta.7)
• First-run assistant, network settings with automatic rollback, name via mDNS (<name>.local), fallback address 192.168.0.32 without DHCP
• HTTPS with a self-signed certificate that follows name and IP, own certificate possible; own certificate authority for the home network and Let's Encrypt over DNS (0.2.0-beta.18)
• Dynamic DNS: DuckDNS, dynv6, Cloudflare, No-IP or any dyndns2 address, IPv4 and IPv6 (0.2.0-beta.18)
• Power schedule: switch off and on per weekday (switching on through the wake-up alarm of the DNS-320L/320 rev B/327L; 0.2.0-beta.15; switching off works from 0.2.0-beta.17, the overview shows the date of the next switch-on)
• Start log: the logs of the last 3 starts are kept on the flash (System → Protokolle → Start-Protokoll), so a box that was unreachable after a start can be looked into afterwards (0.2.0-beta.15)
• Reset button: access reset (5–10 s: network, root password, certificate) or factory reset (≥ 15 s), USB button removes USB drives (beta.9) or copies them into a dated folder (0.2.0-beta.12); the buttons work again on the DNS-320L and DNS-325 (0.2.0-beta.10)
• Messages: RAID, volumes, temperature, SMART, updates, failed cloud jobs and app tasks – in the interface, by e-mail (SMTP) and push (ntfy, Gotify, webhook) (beta.9), Telegram bot (beta.12)
• Terminal in the browser (System → Terminal, root shell, beta.12); Apps, Cloud and Paperless can be switched off (beta.12)
• Services with autostart, fan curve and LEDs, logs, settings backup and restore (JSON, optionally AES-256), messages that can be closed
• Look: light/dark/system, accent colours, tiles or tables, per user; Appearance page in two columns on wide screens (0.2.0-beta.10)
• FAV APPS: favourite apps per account as an icon bar above the overview status, the installed apps and in Mein ShareOS (with names or icons only, 0.2.0-beta.10)
• Mein ShareOS: tab Einstellungen with look and password, storage as a table per drive with own use, limit and free space (0.2.0-beta.11)
• 10 languages: English, German, Chinese, Hindi, Spanish, French, Arabic (right to left), Bengali, Portuguese, Russian (beta.7; more: docs/TRANSLATING.md)
• Time: time zone, NTP on/off with own servers (e.g. the router), sync now, set the clock by hand; the battery clock follows (beta.7)
• SSH/SFTP (Dropbear), rescue system in the initramfs (SSH, flash tools)

D-Link firmware, Alt-F and ShareOS compared (DNS-320L)

	D-Link firmware (ShareCenter)	Alt-F	ShareOS
Last release	1.11 (last version listed for CVE-2024-3273); product end of life	1.0 (Oct 2017); trunk r3935 (basis of ShareOS)	0.2.0 betas (2026), updated continuously
Linux kernel	2.6.31 ¹	3.10.32 (0.1RC4, 2014), 4.4.86 (1.0), 4.14.268 (trunk)	6.18 LTS
Boot loader	Marvell U-Boot 1.1.4	stock U-Boot (unchanged)	stock U-Boot (unchanged, never written)
Build system / toolchain	D-Link GPL sources, uClibc ¹	buildroot 2009.08 fork, GCC 7.4, uClibc-ng 1.0.44 (trunk)	buildroot 2026.08.1 (BR2_EXTERNAL), GCC 15.3, musl 1.2.6
System layout	own image formats	squashfs/jffs2, packages in the flash or on disk	squashfs in UBI + UBIFS overlay for settings and packages
SMB	Samba 3.x, SMB1 ¹	Samba 3.6.25: SMB1 and SMB2 (1.0); Samba 4.15 as an optional package	ksmbd (in the kernel): SMB 2.1/3
NFS	¹	nfs-utils	NFS v4 (nfs-utils 2.8)
SSH	none (only via fun_plug workarounds)	Dropbear (OpenSSH as a package)	Dropbear 2026.91, SFTP
Web interface	ShareCenter UI	BusyBox httpd + shell CGIs	uhttpd + ubus/rpcd (ucode), new interface, light/dark, per user
Configuration	own config files	many scattered files	UCI (OpenWrt style), backup/restore as JSON
Updates	manual upload of a .bin	manual upload of a .bin	online from GitHub Releases, verified, every 6 h checked
File systems	ext3/ext4; FAT32/NTFS via FUSE ¹	ext2/3/4, FAT, NTFS (ntfs-3g), btrfs, LVM2	ext4, Btrfs, exFAT, NTFS (kernel ntfs3), FAT32
RAID	own metadata format ¹	mdadm (RAID 0/1/5, JBOD), LVM	mdadm RAID 1 (mirror), RAID 0, JBOD
USB drives	mounted ¹	mounted on plug-in	mounted on plug-in, safely remove, format (4 file systems)
Users and rights	users, groups, quota ¹	users, groups, quota	users, groups, rights per share, storage limit per user, users with their own web area
Extensions	add-ons (discontinued)	ipkg packages with a web page	app store (ShareOS-Apps): web apps on their own port, system apps (nano, htop, strace, iperf3, bash, Transmission, FFmpeg, MiniDLNA, OpenVPN, Tailscale, autobrr)
Cloud / documents	–	– (single packages)	rclone cloud sync, Paperless-ngx inbox
HTTPS	¹	self-signed or Let's Encrypt	self-signed (follows name/IP) or own certificate
Security	unpatched remote code execution (CVE-2024-3273, CVE-2024-3274); D-Link advises to retire the devices	last release 2017; old kernel and Samba	current kernel and libraries, updates via GitHub
Install	factory	.bin via the D-Link/Alt-F web page	.bin via the D-Link/Alt-F web page + system from USB stick/GitHub, or serial console; back to Alt-F from the web page

¹ Details of the D-Link firmware are taken from vendor pages and community reports and were not checked on a box. Alt-F data from its release notes (legacy/alt-f/NEWS) and build configuration in this repository. Sources: CVE-2024-3273, D-Link storage security notice, DNS-320L boot loader banners.

Installing: flash the ShareOS .bin from the Alt-F or D-Link firmware page; ShareOS then installs its system from a USB stick or from GitHub by itself (since 0.1.0-beta.7, tested on the DNS-320L). The way over the serial console (TFTP boot) stays available. Back to Alt-F works from the ShareOS firmware page. Details: docs/TESTING.md, docs/HARDWARE-DNS320L.md. The backend can be run on a build host with qemu (tests/run-stack-qemu.sh), the web interface with sample data via tests/mock-ubus.py.

Roadmap

• Hardware tests of the current betas, then a public beta
• More native apps in the same store: system apps for the terminal (0.2.0-beta.1), Transmission (0.2.0-beta.4), FFmpeg (0.2.0-beta.5), the media server MiniDLNA and OpenVPN (0.2.0-beta.6), Tailscale (0.2.0-beta.7) and autobrr (0.2.0-beta.9) are there; next Syncthing …
• More of the app platform: "open with" defaults per file type
• Storage: LVM2; RAID 5 only makes sense with three or more disks (the DNS-320L has two bays)
• More devices: hardware tests of the DNS-320 rev A/B; the DNS-327L (Armada 370, ARMv7) needs its own kernel configuration and a tester (#61)

Layout

configs/                 buildroot defconfigs (shareos_<board>_defconfig)
board/dlink/dns320l/     device tree, kernel fragment, rootfs overlay, image scripts
package/                 ShareOS buildroot packages
src/alt-f-utils/         Alt-F device tools (MCU daemon, dns323-fw, sysctrl)
patches/                 hashes/patches for buildroot packages
src/shareos-core/        backend: rpcd ucode plugin, updater, UCI defaults, init scripts
sysapps/                 system apps (native programs and services) for the store
tests/                   host and emulator tests (updater, network, users/shares, storage, cloud/Paperless, qemu stack), UI mock
scripts/                 helper scripts
legacy/alt-f/            the original Alt-F tree, kept for reference

Apps: where to submit what

• Web apps (HTML/JS, run in the browser, use the app SDK) → ShareOS-Apps.
• System apps (native programs for the box, and services/daemons) → here, in sysapps/: they are built with the firmware's toolchain, and a service needs its controller in the firmware. The README there has an example of each kind.

Building

See docs/BUILD.md. In short:

make dns320l
# -> output/dns320l/images/ShareOS-<version>-DNS-320L-rev-Ax.bin