Side-by-side specifications of the Synology RS2211+ and RS2212RP+, from official datasheets. Differences are highlighted.
| RS2211+ | RS2212RP+ | |
| CPU | Dual Core 1.8 GHz | Dual Core 2.13 GHz |
| Cores / threads | 2 | 2 cores |
| RAM (base) | 1GB DDR2 | 1 GB DDR3 |
| RAM (max) | 3GB | 3 GB |
| Drive bays | 10 | 10 |
| Expandable to | 22 | 22 |
| M.2 slots | 0 | 0 |
| Network | 2x Gigabit | 2x Gigabit |
| 10GbE | no | no |
| Max raw capacity | 30TB | 66 TB |
| Hot-swap | yes | yes |
| Form factor | 2U rackmount | 2U rackmount |
| Released | 2011 | 2012 |
The RS2212RP+ is the safer pick if you want the more capable platform: it has the newer/faster CPU, higher RAM ceiling, and a redundant power supply, while the RS2211+ is older and more basic. For storage, both are 2U rack units in the same general class, but neither is a modern 10GbE/M.2 system. If you need built-in 10GbE or M.2 NVMe, choose neither and move to a newer Synology model.