Disk assignments

Disk reservation and ownership

In the FAS270c, each node must have ownership of at least one SES disk in each disk shelf in the system. For example, in a single disk shelf system, Node A could own the disk in bay 0, and Node B would then own the disk in bay 1.

In a factory-configured system, one node has ownership of one SES bay disk and the other node owns the second SES bay disk. In addition, each node has ownership of one parity disk and one spare disk. Node B owns disks 0b.16, 0b.18, and 0b.20, and Node A owns disks 0b.17, 0b.19, and 0b.21. The balance of the disks are unowned.

If you add storage to your FAS270c, it arrives with unowned disks. You must assign ownership of the SES disks to the appropriate node.

Note
You can change the disk ownership pattern after initial setup. For information about how to change disk ownership, see the Storage Management Guide.

The following illustration identifies the SES bays in the FAS270c or in a DS14 family disk shelf.

Disk ownership worksheet

Complete the following worksheet to determine disk assignments for your cluster. Identify any disks for which you want ownership change, and mark in the worksheet which node will own the disk. You should use this sheet to check ownership during the setup process.

Bay	Disk shelf 1			Disk shelf 2			Disk shelf 3
Bay	Disk ID	Node B	Node A	Disk ID	Node B	Node A	Disk ID	Node B	Node A
0	0b.16 SES disk			0b.32 SES disk			0b.48 SES disk
1	0b.17 SES disk			0b.33 SES disk			0b.49 SES disk
2	0b.18			0b.34			0b.50
3	0b.19			0b.35			0b.51
4	0b.20			0b.36			0b.52
5	0b.21			0b.37			0b.53
6	0b.22			0b.38			0b.54
7	0b.23			0b.39			0b.55
8	0b.24			0b.40			0b.56
9	0b.25			0b.41			0b.57
10	0b.26			0b.42			0b.58
11	0b.27			0b.43			0b.59
12	0b.28			0b.44			0b.60
13	0b.29			0b.45			0b.61