Supero SC848 Series, User Manual

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D-12
SC848 Chassis Manual
PRI_J0
PRI_J1
PRI_J2
SEC_J0 SEC_J1
SEC_J2
J17
WWN
SAS HBA
Port A
Expander 1
Port B
Expander 2
SAS HBA
Dual Host Bus Adapter
In a Dual Host Bus Configuration, the
backplane connects to two Host Bus
Adapters (HBA).
Figure D-8: Dual HBA
PRI_J0
PRI_J1
PRI_J2
SEC_J0 SEC_J1
SEC_J2
J17
WWN
SAS HBA
Port A
Expander 1
Port B
Expander 2
SAS HBA
Dual Host Bus Adapter
Failover
If the expander or data path in Port A
fails, the system automatically switches
to Port B. This maintains a full connec-
tion to all drives.
Figure D-9: Dual HBA Failover
D-11 Failover with RAID Cards and Multiple HBAs
The SAS-836EL backplane may be configured for failover with multiple HBAs using
either RAID controllers or HBAs to acheive failover protection.
RAID Controllers: If RAID controllers are used, then the failover is accomplished
through port failover on the same RAID card.
HBAs : If multiple HBAs are used to achieve failover protection and load balancing,
Linux MPIO software must be installed and correctly configured to perform
the load balancing and failover tasks.
IMPORTANT: For RAID controllers, redundancy is achieved through port
failover. For multiple HBAs MPIO software is required to achieve failover
protection.