Ha Storage Configuration - HP StorageWorks NAS 8000 - Version 1.6.X Manual

HA Storage Configuration

This section provides suggestions for configuring the storage on an NAS 8000 with
high availability (HA) features. For a description of HA, see
On a simple dedicated-storage NAS system without HA features, the simplest way to
configure the storage is to create a single LUN for the entire array, then create one volume
group with multiple file volumes beneath it. However, in an HA cluster with two NAS servers,
each volume group can be active on only one NAS server, or node, at a time. Therefore, if you
are using active/active failover packages (see
at least two volume groups so each node can access some of your storage.
In addition, with SAN configurations storage generally resides on several different storage
devices within the SAN. LUNs are created on each array using the SAN management
software. To ensure that a volume group does not become unavailable due to hardware
problems on a specific storage device, the safest configuration is to create a separate volume
group for each LUN.
Note:
failure, the entire volume group will be unavailable. By creating a separate volume group for each
LUN, you are ensuring that only that portion of the storage residing on the failed array will be
unavailable until the array is restored. All other storage will remain unaffected.
When determining how many LUNs and volume groups to create, consider the following:
The illustrations on the following pages depict common storage configurations:
HP StorageWorks NAS 8000 SAN High Availability, Solution Integration Manual (SIM)
When a volume group includes LUNs from multiple arrays, if any one array has a hardware
A volume group can be active on only one node at a time.
A volume group can be assigned to only one failover package.
File volumes can't be split between failover packages or nodes.
Multiple volume groups can be assigned to the same failover package.
A failover package can only run on one node at a time.
The HA cluster is limited to 60 failover packages total (both nodes combined).
A package is the smallest unit of failover.
A volume group is the smallest unit of storage that can be failed over.
If a failover package contains multiple volume groups and a single volume group, file
volume or even share fails, the entire package will be failed over.
More failover packages means a higher degree of granularity to balance the failover
packages between the nodes and detect failures.
More failover packages also results in higher complexity in the cluster configuration and
requires more virtual IP addresses to keep track of.
The failover packages should be divided between the cluster nodes such that the storage
access load (from client systems) will be balanced. This may or may not correspond to
balanced storage capacity between the nodes.
One LUN and one volume group (for active/passive failover).
Multiple LUNs, volume groups and failover packages (most common for SAN
configurations).
Network and Storage Planning
Physical Storage
Failover Packages on page 14), you must create
on page 12.
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