HPP Enterprises P4000 SAN - Manual (Page 34)

34
logical volumes. With Network RAID, which is configurable on a per-volume basis, data blocks are
written multiple times to multiple nodes. In the example shown in Figure 26, Network RAID has been
configured with Replication Level 2, guaranteeing that a volume remains available despite the failure
of multiple nodes.
Figure 26. The storage cluster is able to survive the failure of two nodes
Configuring Network RAID
You can set the Network RAID configuration for a particular volume either during its creation or by
editing the volume’s properties on the Advanced tab, as shown in Figure 27. You can update
Network RAID settings at any time without taking the volume down.
The following Network RAID options are provided:
 2-Way – Up to one adjacent node failures in a cluster as seen above
 3-Way – Up to two adjacent node failures in a cluster
 4-Way – Up to three adjacent node failures in a cluster
The number of nodes in a particular cluster determines which and how many nodes can fail, based
on the selected Network RAID configuration.