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ewwhite / zfs-ha

ZFS High-Availability NAS
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JBOD Redundancy #18

Closed terminet85 closed 5 years ago

terminet85 commented 6 years ago

What would be the best strategy in order to redound also he JBOD?

ewwhite commented 6 years ago

It depends upon how you design the pool, your raid level and your risk profile.

For instance, if you use RAID mirrors, you can arrange each side of the mirror into a different JBOD.

SAS cabling is important. Multipath is important. But in practice, the incidence of complete JBOD failure is rare.

mwpastore commented 6 years ago

Keep in mind that most JBODs have quite a bit of redundancy built into them: redundant power supplies, redundant I/O modules, etc. The only "single point of failure" is the backplane itself, i.e. the circuit board that the drives and I/O modules plug into.

ewwhite commented 6 years ago

Right, and at a certain scale, you have to rely on the track record of the storage enclosures. It's difficult to plan/spread your vdevs across multiple cabinets in a way that would sustain enclosure failures.