User manual

iSCSI GbE to SAS/SATA II RAID Subsystem
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User Manual
4. Single: Single controller mode. In the stage, the controller must stay in slot A.
Boards for SATA drives are not necessary. The differences between single and
degraded are described on the following. There is no error message for inserted one
controller only. I/O will not force to write through. And there is no ownership of RG.
Single controller mode can be upgraded to dual controller mode, please contact the
distributor for upgradable.
In addition, iSNS server is recommended. It’s important for keeping I/O running
smoothly when RG ownership is switching or single controller is failed. Without iSNS
server, when controller 1 fails, the running I/O from host to controller 1 may fail because
the time which host switches to the new portal is slower than I/O time out. With iSNS
server, this case would not happen.
NOTE: iSNS server is recommended for dual controller system.