As I originally blogged, I was hoping to use EMC snapshots to perform server-less/network-less backups…
To make a long story short, Replication Manager is useless for LUNs with ZFS. According to EMC, this won’t change in the near future. PowerSnap also has no support for taking snapshots of LUNs with ZFS on them so basically…

When discussing availability of a service, it is common to hear the term “Five Nines” referring to a service being available 99.999% of the time but “Five Nines” are relative.
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In reality, none of those calculations are relevant because no one cares if a service is unavailable for 10 hours, as long as they…

The following table shows the difference between 146GB RAID 5 IOPS/TB and 300GB RAID 10 IOPS/TB.
Each column represents a different Read percentage (the Write percentage is the inverse).
Negative numbers mean that for this Read percentage and IOPS requirement, RAID 10 gives more IOPS/TB of disk. Positive numbers mean that RAID 5 gives better…