Most business NAS devices, such as Synology and QNAP, use RAID so that one disk can fail without losing data. That only works if someone notices the failure and replaces the disk before a second one fails.
How a failed disk gets noticed
When the NAS sits in the office, it beeps. Staff hear it, and some even film it and send us the video. That is enough for us to confirm the fault and quote a replacement disk.
When the NAS is in a data center, at a remote site, or in a soundproofed server room, nobody hears anything. The NAS can run with a failed disk for days or weeks, and no one in the office knows.
Why the delay matters
In a common single-parity setup (RAID 5 or SHR), the volume survives one failed disk but has no protection left. If a second disk fails before the first is replaced, the whole volume is lost. Rebuilding onto a new disk also puts heavy load on the remaining disks, so the time spent degraded is the riskiest period.
What our scheduled health check does
On Synology and QNAP units, we run a script that emails a plain-language report to our team on a regular schedule. It covers:
- Health status of each disk
- RAID or storage pool state: healthy, degraded or rebuilding
- Volume space, with a warning when it is running low
- System temperature and fan status
- Blocked login attempts (Synology) and the installed firmware version (QNAP)
If a disk has failed, it shows up in the next report, even when nobody can hear the NAS. We can then quote the replacement and arrange it before a second disk fails.
What it doesn’t do
It doesn’t predict every failure, and a disk can fail between checks. RAID is also not a backup. A NAS still needs a separate backup that is tested regularly, which is the purpose of our Backup Assurance service.
Five questions to ask about your own NAS
- Where is it, and would anyone hear an alarm?
- Are email alerts set up, and has anyone tested them?
- What RAID type is it, and how many disks can it lose?
- Is there a plan for a replacement disk, with a quote you could approve quickly?
- Is there a separate backup, and has a restore been tested?
If you’re not sure about any of these, talk to us. You can also see how we handled proactive monitoring and backup assurance for a client.