Expansion units

When the bays run out, an expansion unit adds more without migrating a byte. DX units pair with DiskStation, RX and RXD with RackStation, FX with FlashStation. Each page lists the compatible hosts.

Popular

DX525

Synology DX525 5-bay expansion unit

Seamless capacity expansion for Synology DiskStation

$1,021.00inc. GSTIn stock

DX517

Synology DX517 5-bay expansion unit

Effortless capacity expansion for Synology DiskStation solutions on-the-fly.

$1,021.00inc. GSTIn stock

RX418

Synology RX418 4-bay expansion unit

4-bay 1U rackmount expansion unit for 1U RackStation

$1,328.00inc. GSTOnly 1 left

RX426

Synology RX426 4-bay expansion unit

Reliable 4-bay storage expansion for RackStation

$1,339.00inc. GSTOnly 1 left

Add bays without migrating

An expansion unit connects over eSATA or Infiniband and appears as extra bays in DSM. You can extend an existing storage pool across it or keep it as a separate pool for backups. DX517 and DX525 pair with DiskStation Plus models, RX418, RX426 and RX1223RP with RackStation, RXD1219sas and RX1222sas with the SA series, FX2421 with FlashStation. Each listing names the hosts it supports.