A reader emailed me last spring after his Synology DS920+ went dark two minutes into a DSM update. No beep, no blue blink, just a dead front panel and a spinning fan. He had 6TB of family photos on it and no backup, because the update had felt like a two-minute chore he could squeeze in before dinner.
It usually is. Firmware updates on a modern NAS succeed something like 99 percent of the time, quietly, in the background.
The problem is that 1 percent, and the fact that almost every disaster I have helped untangle was preventable with about fifteen minutes of prep. So here is the run-through I do on my own boxes and the ones I fix for other people, in the order I actually do it.
1. Confirm you have a real backup, not a RAID array
This is the check people skip, and it is the only one that truly matters. RAID protects you against a dead drive. It does nothing when a botched firmware flash corrupts the volume or the whole unit stops booting.
Before anything else, verify that a copy of your important data exists somewhere the NAS cannot take down with it: an external USB drive, a second NAS, or a cloud tier. If you want the difference spelled out properly, Backblaze has a clear write-up on RAID versus backup that I send people constantly.
2. Read the release notes, actually read them
Every DSM and QTS release ships with notes, and they are short. Look for two things: known issues, and any line that says the update is being rolled out in stages.
Synology in particular pushes big DSM versions gradually, so the version your neighbor has may not be the one offered to you yet. If the notes mention a bug affecting your exact model or a package you rely on, that is your cue to wait a week and watch the community forums.
What counts as a red flag
Phrases like "users may experience" or "we recommend backing up before installing" are not boilerplate. When a vendor bothers to warn you in the notes, believe them.
3. Note your current version before you change anything
Write down the exact firmware version you are on right now. On DSM it is under Control Panel, Info Center. On QTS it is in the top-right dashboard.
If the update goes sideways and you need support, the first thing anyone will ask is what version you were running. Having it written down also lets you request the previous installer if you decide to roll back.
4. Check package and app compatibility
This is where the quiet breakages happen. A major version jump, say DSM 6 to DSM 7, can retire packages or force logins to change.
Make a quick list of what you depend on: Plex, Docker containers, Surveillance Station, Hyper Backup, any VPN server. Then confirm each one supports the target firmware. Plex famously lagged behind DSM 7 for weeks, and plenty of people updated blind and lost their media server until an update landed.
| Package type | Risk on major update | What to check |
|---|---|---|
| Media (Plex, Emby) | High | Vendor has a build for the new OS |
| Docker containers | Medium | Container Manager rename, path changes |
| Backup tools | Medium | Existing tasks still recognized |
| Vendor apps | Low | Usually updated alongside firmware |
5. Export your configuration
Both Synology and QNAP let you export a settings file in a few clicks. On DSM it is Control Panel, Update and Restore, Configuration Backup. This saves users, shared folder permissions, and most settings.
It takes thirty seconds and it is the difference between a five-minute recovery and rebuilding your whole config by memory. I keep the exported file next to my data backup, never on the NAS itself.
6. Check drive health first
A firmware update puts the drives through a shutdown, a boot, and often a filesystem check. A drive that is already limping is far more likely to fail during that stress than during idle Tuesday afternoon.
Open Storage Manager and look at the SMART status and the volume health. If any drive shows warnings, reallocated sectors climbing, or the pool is in a degraded state, fix that before you update. Never update on top of a rebuild in progress.
7. Pick the right time and stay near the box
Do not start an update at 11pm before a workday, and do not start one remotely from a coffee shop. Updates usually take 10 to 20 minutes and the NAS reboots itself, sometimes twice.
If something hangs, you want physical access to power-cycle, read the beep codes, or plug in a monitor. A reboot that stalls for 40 minutes is recoverable if you are standing there; it is a panic if you are three hours away.
8. Protect against power loss
Losing power mid-flash is one of the few things that genuinely bricks a unit, because it can corrupt the firmware image while it is being written.
If you own a UPS, confirm the NAS is plugged into the battery side and that the battery actually holds a charge. No UPS? At minimum, avoid updating during a thunderstorm or when the grid in your area is flaky, and check that no one is about to run the microwave on the same circuit that keeps tripping.
9. Disable auto-update if you want control
By default many boxes install security and minor updates automatically. That is fine for small patches, but it means a firmware change can land at 3am without you running this checklist.
In DSM under Update and Restore, you can set it to only download updates and notify you, or to auto-install DSM updates but not major versions. Choose the level of surprise you are comfortable with. I let mine auto-install small security patches and hold the big version jumps for a manual, prepared install.
10. Do the update, then verify
Now click it. Watch the progress, let it reboot fully, and log back in.
Once you are in, do not walk away yet. Check that your volume mounted healthy, that your key packages started, and that a couple of shared folders open and read correctly from another device. Spend five minutes confirming the thing works before you consider the job done.
If you use Docker heavily, open Container Manager and confirm your containers came back up rather than sitting stopped.
If it went wrong
If a package broke, most vendors let you downgrade that individual app without touching the firmware. If the firmware itself is the problem and you noted your old version in step 3, you can often download the previous installer and manually install it through the update page. Recovery mode and the vendor's desktop finder tool are the next steps if the web interface never comes back.
The fifteen minutes that saves your weekend
None of this is hard, and after you do it twice it becomes muscle memory. Backup, notes, version, compatibility, config export, drive health, timing, power, auto-update setting, then verify.
The reader with the dead DS920+ eventually recovered most of his photos through a data-recovery shop, at a cost of just over 400 dollars and three weeks of waiting. Fifteen minutes with a checklist would have made that entire ordeal a non-event, and that is the whole point of running one.
Frequently asked questions
How long does a NAS firmware update usually take?
Most DSM or QTS updates finish in about 10 to 20 minutes, including one or two automatic reboots. Larger major-version jumps can take longer because of file system checks and package migrations. Plan for up to 45 minutes and do not start one when you need the NAS again immediately.
Can a firmware update really brick my NAS?
It is rare but possible, usually from power loss during the flash or an already-failing drive dying under the stress of a reboot. The firmware image itself can corrupt if writing is interrupted. This is exactly why a UPS, a healthy drive check, and a real backup are on the list.
Should I update as soon as a new version appears?
Not for major versions. Vendors roll big DSM and QTS releases out in stages and early builds sometimes have bugs that get patched within a week or two. For minor security patches, updating promptly is fine and usually recommended. For a jump like DSM 6 to 7, waiting and watching the forums is wise.
Will an update delete my data or settings?
A normal firmware update leaves your data and settings intact. The risk is not deliberate deletion but corruption if something goes wrong mid-update, or a package that stops working on the new version. Exporting your configuration and having a data backup protects you against both scenarios.
How do I roll back if the update causes problems?
If a single package broke, downgrade just that app rather than the whole firmware. If the firmware itself is at fault, download the previous version's installer from the vendor and install it manually through the update page. This is why you should note your old version number before updating.
Do I need a UPS to update firmware safely?
It is strongly recommended but not mandatory. A UPS protects against the one failure that genuinely bricks units: power loss during the flash. If you do not own one, at least avoid updating during storms or on an unreliable circuit, and consider a UPS a worthwhile 60 to 120 dollar purchase for any NAS holding data you care about.
