High Availability Information - HP 2000sa Deployment Manual

3 High availability information

HP External SAS BladeSystem Solutions provide high availability, offering c-Class BladeSystem
users full connectivity to External SAS storage by using the following redundant hardware
components:
Two controllers in each MSA2000sa controller enclosure
Two I/O modules in each MDS600 storage enclosure drawer (four per MDS600 storage
enclosure)
Two HP 3Gb SAS BL Switches in each BladeSystem c-Class enclosure (four when using
double-density server blades in the c7000 enclosure)
One dual-ported P700m Controller (four links configured as two (2X) SAS ports) in each server
Dual-ported SAS drives in the MSA2000sa controller enclosures and drive enclosures
Redundant power supplies and fans in the BladeSystem c-Class enclosures and MSA storage
enclosures.
Using redundant components ensures high availability. If any component in the path between the
server and the storage fails, management software will automatically fail over all I/O to the alternate
path.
Although single-controller MSA2000sa controller enclosures and single I/O module MDS600
drawers are supported for use in single-domain environments, the dual-controller/dual I/O module
models are required in high availability environments. With two controllers in the controller
enclosure, or two I/O modules in the MDS600 drawer, high availability is ensured if one of the
controllers/I/O modules fails. During a failover event, all processing is performed by the remaining
controller/I/O module, with no interruption to the flow of data.
When configuring the storage, the storage enclosures offer a variety of RAID levels, allowing a
user-selected level of performance and fault tolerance. For more information about RAID levels and
configuring the MSA2000sa storage, see the HP StorageWorks MSA2000sa Configuration Best
Practices White Paper at
information about RAID levels and configuring the MDS600 storage, see the Configuring Arrays
on Smart Array Controllers Reference Guide, at
proliantstorage/software-management/acumatrix/.
Although beyond the scope of this document, clustering is supported in BladeSystem environments,
providing another level of fault tolerance. For more information about clustering support for the
MSA2000sa, see the QuickSpecs on the MSA2000sa website: http://www.hp.com/go/msa.
For more information about clustering support for the MDS600, see the QuickSpecs on the MDS600
website: http://www.hp.com/go/mds600.
http://www.hp.com/gp/msa2000sa (under Resource Library). For more
http://h18000.www1.hp.com/products/servers/
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