DSM 7.3/7.4 Note ⚠️

Read before update to DSM 7.3/7.4:
- Starting with DSM 7.3, Synology will officially drop support for older hardware. (Missing movbe support by CPU)
- Starting with DSM 7.4, Synology will officially drop support for older hardware. (Missing movbe and bmi2 support by CPU)
-> These changes are made by Synology and there are enough discussion around how they did to bypass this for their own "unsupported" systems

Update Note ⚠️

For Loader before 4.0.0 and 4.0.0 beta:
- A full clean installation of DSM is RECOMMENDED but you can try to update it. (Don't forget to backup your Data before you format the disks!)
- It will be like a complete rebuild of Arc -> Replace Bootimage and reconfigure to get all working
- Reselect the model and configure again to add missing parts.
- DSM 7.0/7.1 is not supported by loader anymore

✨ Arc & Arx — Update

Arc 4.1.0 → 4.2.1

Arx 1.0.0 → 1.1.1

Addons 26.09.26 → 26.10.27

Modules 26.09.06 → 26.10.19

LKMs 26.09.20 → 26.10.18

Custom 26.09.25 → 26.10.27

Arc Control 4.5.1 → 5.0.24

Arc/Arx Flash 1.0.4 (new)

Four weeks of making things just work: a static IP for every network card, disks that finally go to sleep, a "Format Disks" that really starts fresh, notifications rebuilt from the ground up, a custom kernel choice that sticks, and an end to the "Welcome back" loop. Arc Control becomes a health monitor for your NAS, Arx gets its first numbered releases, and there is a new tool to flash and update your loader stick.

📦 Arc (Loader)

🌐 Network

A static IP for every network card — for the loader and for DSM. Each card can stay on DHCP or get a fixed address. Arc checks address, netmask and gateway before saving, and you can apply it right away or with the next reboot
A static address in the loader now really sticks. Before, the loader's DHCP client quietly put its own address back
Network card order is always on. Every port keeps the same name (eth0, eth1 …) in the loader and in DSM. Cards are sorted by where they sit in the machine, USB adapters last. The NIC Order menu shows up whenever there is more than one card, and configuring no longer asks about it
Netfix is gone — it is not needed anymore, since all of the above is now the default. Existing configs are cleaned up automatically
Cards in higher slots (0a, 0b …) are no longer sorted in front of slot 09
Faster start with several network cards. The loader now waits for all cards at the same time instead of one after the other, 60 seconds at most. A connected card that gets no address no longer holds up the start. If your network is slow to hand out addresses, the wait can be set to 90 or 120 seconds in the menu
Every card in DSM gets its own MAC address. Two cards could end up with each other's MAC in DSM. Machines with more than four network cards now get all their MAC addresses in DSM, not just the first four

🔄 Updates

Update Loader now also updates the boot manager (GRUB), not just its menu
Updates run unattended from start to finish. Two places could still stop and wait for someone at the screen — asking for MAC addresses, or after a failed download. If a download or check fails, Arc now says why and simply starts DSM with the build it already has. Failed downloads are retried
After a loader update, all modules of the new release are selected. Before, the next build asked for modules that no longer existed and missed new ones
Offline Mode no longer switches itself on. It was decided by a GitHub check that only allows 60 requests per hour, so a loader with internet could come up "offline" — and switching it off in the menu turned it right back on. Arc now checks once per boot, and your choice sticks
Timezones with two slashes (like America/Argentina/Buenos_Aires) are set correctly

💾 Install & Disks

"Format Disks" now really wipes the disks. Old partition tables and RAID information were left behind, so the DSM installer found the old system, kept its settings and skipped installing the built-in packages — Storage Manager included. Disks are now wiped completely, the same way Arx does it
DSM's extended partition (the one that holds your data partition) is no longer offered for formatting on its own — wiping it would have destroyed the data inside
No more "Welcome back" loop. If DSM was installed from its own online download (no .pat uploaded), it failed a version check on every boot and showed "Welcome back" with Restore — and Restore did not help. Fixed (found on Arx, fixed in both)
DSM config backups are read from their new location; backups made by older versions can still be downloaded
Clone Loader works like Arx now. It copies the whole loader disk as it is, only offers disks that can take it, and tells you when a copy fails instead of reporting success
Rebuilding from Arc Control no longer ends in "Disk not installed". A rebuild started from inside DSM could leave every addon unable to start. Fixed in Arc and Arc Control

🐧 Custom Kernel & Models

Your custom kernel choice is kept when you change the DSM version. Before, it quietly went back to Synology's kernel. It now only does that if the new version has no custom kernel
The menu always shows the kernel that will really be used
epyc7003 and icelaked can choose the custom kernel on DSM 7.4, and epyc7002 now on DSM 7.2 as well
There is one custom kernel now: legacy. "full" and "upstreamed" are gone; configs that used them switch to legacy automatically
Random serial numbers and MAC addresses look like real ones. For models without Arc Patch, they now follow Synology's own pattern for that model
RAID and SCSI controllers are shown as experimental on all Linux 5.x models, and HBAs no longer show a warning there

🚀 Boot

Machines no longer get stuck at the boot menu. On boards with a serial port and nothing connected to it, electrical noise could stop the countdown. The menu is still shown on serial, but only the keyboard can interrupt it
New "DSM (Arc <version>) is booting" message right before DSM starts. Webhook and Discord messages give up after 15 seconds, so an unreachable server can never hold up the boot
Fixed a build step that could fail while preparing the kernel (thanks to Sven Dreier)

🔔 Notifications

Webhooks from DSM work again. The setting was read from the wrong place, so DSM never sent one. Discord webhooks are fixed as well
Notifications are now built in and replace the old notify and updatenotify addons. They are always installed; old configs are cleaned up automatically
The loader's webhook/Discord settings are only for the loader's own messages (before DSM is running) and no longer need a rebuild. Where DSM sends its notifications is now set in Arc Control

🎨 Web UI

A new look, shared with Arx and Arc Control: a cleaner sidebar with line icons, rounder cards and dialogs, and a new sign-in page
The file manager matches the new look and follows the light/dark switch
Dark mode no longer flashes white while the page loads

🗑️ Cleanup

An addon that is not available for your platform is now really removed from the config, instead of being looked for again on every build
diskcompat is no longer a default addon — it is part of hdddb now
The .vhd download is gone. For Hyper-V use the .vhdx, or one of the other images

🧭 Arx

Arx — the evolution of Arc, set up entirely in the browser — got its first numbered release and is at 1.1.0 now.

Arx 1.0.0. Arx moved from date versions (26.10.xx) to numbered releases. DSM systems built with a date-versioned Arx are told about the new releases too
Your own serial number and MAC addresses. In advanced mode you choose: Arc Patch, a random serial and MACs, or your own. Your own MACs are set per connection on the Network page
More models: epyc7003 and icelaked (marked beta), and the remaining geminilakenk, r1000nk and v1000nk models — all without Arc Patch
Arx only offers DSM versions it can really start: 7.4.0 and newer, on epyc7003 and icelaked 7.4.1 and newer
Back up and restore the hardware key (DSM Options, advanced mode). A new loader stick needs it to unlock DSM's encrypted shared folders
DSM Recovery Mode, as in Arc — in the boot menu and in the power menu. Reinstall and Recovery are only offered when there is a current build
Older CPUs start again, like the Intel Atom D2550 or the AMD CPU in the HP N54L
The power button works again
Some network cards had no link in Arx on UEFI machines (for example Intel 10GbE on a Dell R340). Fixed
Arx waits up to 60 seconds for an address instead of 20, and a connected card without an address no longer holds up the start. More than four network cards all get their MAC addresses in DSM
Downloads check the connection first and name the server if it cannot be reached, stop when they stall, and show their speed
If the rebuild after a DSM update fails, the page now says why
Paste into the web terminal from the menu or with Shift+Insert
A new glass look, shared with Arc Control
DSM updates are handled on the next start. If DSM updates itself, Arx notices, patches the update's boot files and starts DSM — no rebuild and no network needed
Network at a glance. Every connection with the address, gateway and DNS it has right now. In advanced mode each card can get a static address, used by Arx and DSM alike. The address belongs to the card, not to a name like eth0, and eth0 in Arx is eth0 in DSM
Tested on more hardware. Arx has now been run on a small set of real machines and VMs, not only VMware
Everything in the Addons section below applies to Arx as well — sleeping disks, M.2 cards, drive compatibility and more
Notifications now say which loader booted DSM, e.g. "DSM (Arx 1.0.1) is running @ …"
LED control and notifications find Arx's settings, so UGREEN LEDs and Arc Control's alerts work on Arx too
The documentation now covers signing in, the boot menu, network, advanced mode, power and fans

🧩 Addons (Arc & Arx)

💤 Disks Can Sleep Again

SATA disks spin down again. A disk temperature sensor asked the disks for their temperature every few seconds (for the fan curve), which kept them awake around the clock. DSM reads disk temperatures itself, so the sensor is no longer used
A disk check that was meant to leave sleeping disks alone woke them up first. Fixed
powersched wrote a log line every minute, which kept every data disk awake. It is now filtered out (reducelogs)

💾 Disks & Storage Manager

Generic M.2 adapter cards work properly (QNAP QM2 and other ASM2824-based cards). DSM mistook them for a Synology FX2422N, so the drives got no M.2 slot or showed as "unverified". They now show up as normal M.2 drives. addincards is only needed for Synology's own cards now
Onboard SATA comes first. On machines with onboard SATA plus an HBA, the onboard disks could end up as Drive 7–10 behind the HBA. Now it is onboard first, then HBAs
Disks behind an HBA are ordered by their bay and keep matching their slot
Faster boot. Several services waited 30 seconds each — about a minute in total — for disks that were already there. Most noticeable on VMs (VMware, VirtIO) and on the first boot after an install or model change
Fixed a startup conflict that could leave your storage pool unassembled and all packages stopped. It was caused by the apppatch addon, which has been removed
Storage Manager's disk panel and the compatibility checks now wait until all disks are mapped, so a slow disk is no longer skipped until the next boot
Drives no longer show as unsupported on DSM 7.4
Disks that take long to spin up are no longer missed at boot

✅ Drive Compatibility (hdddb)

Drives no longer flip back to "Not verified" after the first boot. DSM installs an online update pack during the first boot that overwrote hdddb's changes. hdddb now runs after it
diskcompat is now part of hdddb — one addon instead of two. Configs that still list diskcompat keep building
The check no longer fails because of drives that are not even in your NAS
On a first boot the check could fail because DSM's storage service was not ready yet. It now waits and retries
No more "dhm_tool is not installed" / IronWolf errors in the log
Every run is written to /var/log/hdddb.log, so problems during a first boot can still be looked at afterwards

🔔 Notifications

All settings are in Arc Control now — alerts, limits and DSM's own notifications. Only the update and boot alerts are on by default
One daily update check replaces updatenotify's reminder every two hours

🌐 Network (DSM)

Static IPs in DSM fixed: they now work with Open vSwitch (the address used to land on eth0) and bonds, each card goes back to DHCP when its static address is removed, and DNS and gateway are no longer lost
sortnetif is always installed now and no longer listed in the addon selection; netfix was removed
Hyper-V: DSM could start without eth0. Fixed
"Reboot to loader" now also works from the DSM installer and from recovery mode

🛡️ After DSM Updates

Addons no longer put back files from an older DSM version. After a DSM update or a model change, several addons restored a backup taken on the old release. Backups are now tied to the DSM version they came from
No more 502 errors on the login page at boot (cpuinfo), and an old web server config no longer comes back after a DSM update
DSM config backups (dsmconfigbackup) are now stored on the loader's third partition, old ones are cleaned up properly, and a failed unmount can no longer wipe the loader partition

💡 Hardware

UGREEN iDX6011 Pro: the new fan driver is loaded automatically (see Custom Kernel)

🐧 Custom Kernel (epyc7002 / epyc7003 / geminilakenk / icelaked / r1000nk / v1000nk)

🆕 Two New Platforms

epyc7003 and icelaked now get the custom kernel too (DSM 7.4 only). Both keep what makes them different in Synology's own kernel — epyc7003 its SAS HBA and multipath support, icelaked its Intel sensors and IOMMU — and get the same extras as epyc7002 on top: GPU drivers, Realtek network cards and more
epyc7002 can use the custom kernel on DSM 7.2 as well

🛡️ Based on DSM 7.4-90080, with 5,000 Linux Fixes

The custom kernel now uses Synology's DSM 7.4-90080 kernel source. The old 7.4 build tools were pulled by Synology and can no longer be downloaded
About 5,000 fixes from the Linux long-term branch are now included — security and stability fixes for filesystems (btrfs, ext4), networking, USB, storage and more, collected from 2021 to today. A handful were left out on purpose, because they would break DSM's own prebuilt drivers
Fixed crashes that came with these fixes in 26.10.24. A few of them did not fit DSM's own prebuilt parts — snapshots and LUNs could crash, and so could parts of networking. They are taken out again
Realtek (r8125, r8126, r8127, r8168) and QLogic network cards work in the DSM installer. They could fail to load while installing DSM

💻 Virtual Machines

Proxmox's default LSI SCSI controller (LSI 53C895A/53C810) and QEMU's AM53C974 are now supported
Windows VMs in Virtual Machine Manager are more stable. Two fixes for Windows guests that could crash with a blue screen (0x0A) or hang
When a VM touches a CPU feature the hypervisor does not know, it is now logged, so blue screens like 0x3D on newer hosts can finally be traced

⚡ Thunderbolt / USB4

Thunderbolt now starts on Intel Tiger Lake and newer (Alder Lake, Raptor Lake, Meteor Lake, Arrow Lake). The controller was found but never came up
AMD USB4 hosts (Ryzen AI / Strix) work. They were detected, then stopped responding after the first packet
On AMD, devices plugged in after boot are detected now, and no longer fall back to a slower mode

💨 Fans

Fan control for the UGREEN iDX6011 and iDX6011 Pro — DSM could not drive their fans at all. The Pro's fans were also hidden in DSM, because the model name is replaced at boot; the driver now reads the real one
Fan control for the Minisforum N5, N5 Pro and N5 Air (untested on the hardware)

🔌 Network & USB

Aquantia/Marvell AQC 10GbE cards no longer log "Driver has suspect GRO implementation" and TCP behaves as it should. Same speed as before; the hardware feature behind it is just off by default now
Mellanox cards: a leftover DSM driver could mix with ours and crash once a Mellanox card was fitted. Fixed
Many more USB serial adapters (USB-to-RS232/RS485 dongles) and LTE/GSM modems for SMS gateways. Zigbee, Thread and Z-Wave sticks were already supported
eMMC tools (like mmc-utils) work again instead of failing on every multi-command request

🖼️ Graphics

Graphics driver backport (Apex) updated to 2026.02.3
AMD Ryzen AI 300 (Strix Point) and Ryzen AI 9 465–475 (Gorgon Point): the missing driver support and firmware have been added (untested on the hardware). Strix Halo, Krackan Point and RDNA 4 are not supported yet
Intel Arrow Lake graphics runs on the i915 driver (untested). Lunar Lake and Panther Lake still are not supported

⚙️ Closer to Synology's Own Kernel

Drivers that Synology builds into its kernel — CPU temperature, SMBus, the USB controller on r1000nk/v1000nk — are now built in again instead of being separate modules
Loop devices are available right from the start

ℹ️ Good to Know

PS/2 keyboard support is no longer included, to match Synology's kernel — this mainly affects VM consoles that emulate a PS/2 keyboard
There is no longer a framebuffer console inside DSM (also on Hyper-V and Xen). Hardware transcoding through the GPU is not affected
IDE disks are not supported — DSM itself has no IDE support, so the loaders no longer show IDE disks either. In Proxmox/QEMU, attach your disks as SATA, SCSI or VirtIO; on Hyper-V, use a Generation 2 VM; on bare metal, set the SATA controller to AHCI

🧰 Tools

⚡ Arc/Arx Flash — new

Flash writes Arc or Arx to a USB stick. Update puts a newer release on an existing loader stick and keeps its settings, the DSM partition and your files
One file, nothing to install — Windows, macOS (Apple silicon and Intel) and Linux
Checks for its own updates

🎛️ Arc Control 5.0

System Health on the Overview. One card shows whether anything needs attention — temperatures, disks, storage and RAID. A warning can be cleared and only comes back if it gets worse
Storage checks. "Check all data" reads every file on a volume, shows its progress and can be stopped. Damaged files are listed by name, old errors are shown in amber and only new ones in red, and errors that need nothing done can be cleared
System History: charts from 1 hour to 30 days, collected in the background
Your own dashboard: cards can be moved and resized on the Overview, Monitoring and Health & History pages
The widget lets you choose its rows, shows System Health, fan, disk and NVMe temperatures and the network, and updates itself
Alerts with your own limits. DSM's notification settings now live here: alerts, their limits, webhook and Discord. Only the update and boot alerts are on by default
Backups: snapshots of the loader configuration, the encryption key, DSM's config backup and a full image of the loader stick
Driver Check on the Debug tab shows which hardware has a driver
Fewer false alarms: a disk is only reported as failing when it fails its own self-check, and messages from DSM's start no longer count as disk errors
Disks stay asleep while Arc Control is open, and Standby is shown correctly
The GPU card shows the real clock speed, and Standby while an Intel GPU sleeps
Sign in with SSO and with directory (domain/LDAP) administrators
A read-only monitoring API, with an example for ioBroker
Loader updates show their release notes properly, the progress bar only moves forward, and Arx's Update & Rebuild no longer says "Finish" before the rebuild is done
Click a disk's name to see its UUID. The M.2 preview in Storage Manager is no longer blocked by ad blockers
A new glass look, plain language everywhere and more help

🔧 Arc Utils

App Installer 1.6.10: fix for Surveillance Station 9.3.0, MailPlus Server 4.0.1 added, Active Backup for Business 3.2.2
The benchmark script recognises Arx