Doing Volume Replication n:1 is not possible now.

What do you mean with this, iSCSI HA is possible.

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We are interested in fully redundant system based on Windows 2008 Hyper-V cluster and storage cluster (iSCSI failover replication). No single point of failure.
Since Open-E still doesn't support this, yet, we are planning to use sync volume replication just for backup purposes (for now).
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