| distro | kernel version | mdadm version |
| Ubuntu 6.06 LTS | 2.6.15 | 1.12.0 |
| Ubuntu 7.04 | 2.6.20 | 2.5.6 |
| Ubuntu 8.04 LTS | 2.6.24 | 2.6.3 |
| Ubuntu 8.10 | 2.6.27 | 2.6.7 |
| Ubuntu 9.04 | 2.6.28 | 2.6.7.1 |
| Ubuntu 10.04 LTS | 2.6.32 | 2.6.7.1 |
| Ubuntu 10.10 | 2.6.35 | 2.6.7.1 |
| Ubuntu 11.04 | 2.6.38 | 3.1.4 |
| Ubuntu 12.04 | 3.2.0 | 3.2.3 |
| CentOS 4.5 | 2.6.9 | 1.12.0 |
| CentOS 5.0 | 2.6.18 | 2.5.4 |
| CentOS 6.0 | 2.6.32 | 3.1.3 |
| Debian 4.0 | 2.6.18 | 2.5.6 |
| Debian 5.0 | 2.6.26 | 2.6.7.2 |
| Debian 6.0 | 2.6.32 | 3.1.4 |
| Fedora 7 | 2.6.21 | 2.6.1 |
| Fedora 15 | 2.6.38 | 3.1.5 |
MDADM 2.x on kernels >2.6.17 supports online resizing of RAID 5 arrays :)