A small business server runs a mix of jobs on a modest budget, so the best RAID balances resilience, performance and capacity without over-spending. Here's a practical layout — size it in the RAID calculator.
Match RAID to the role
Most SMB servers do a bit of everything: file shares, a line-of-business app or database, maybe a few VMs. A sensible default is a small mirror (RAID 1) for the OS/boot, and for the data either RAID 10 (if there's a database or VMs that need write performance) or RAID 6 (if it's mostly file storage and capacity matters).
If the box is purely a file/NAS server, RAID 6 or RAIDZ2 gives the best capacity-with-resilience. If it runs a busy database or several VMs, RAID 10 on SSD is worth the capacity trade-off for the write performance and fast rebuilds.
Don't skip the spare and the backup
On a small array every drive matters, so add a hot spare if the chassis allows — it starts the rebuild automatically and shrinks the risky window (see hot spares). On large drives, prefer dual parity so the array survives a URE or a second failure during that rebuild.
And budget for backup from day one: a small business server is exactly where a single RAID array gets mistaken for a backup. Follow 3-2-1-1-0 with an off-site, immutable copy — ransomware hits SMBs hardest.
Right-sizing without over-spending
SMB budgets are real, so size to need plus sensible growth, not to a vendor's maximum. Use the calculator to compare a RAID 10 SSD layout against a RAID 6 HDD layout on the same budget — you'll often run the database/VMs on a small flash RAID 10 and bulk files on a larger RAID 6, getting the best of both.
New or refurbished, Servnet sizes and supplies the server, the array and the backup as one — use the tools to frame it, then get a quote.