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Cluster Disk Bandwidth (rc01-rc60)
Note 'rcXX-2' indicates the second disk. rc01-rc40 have a WD2503ABYX enterprise disk in the first slot and a desktop Seagate ST3500418AS in the second. rc41-rc60 have only WD disks (which is pretty obvious in the fans high graph).
Fans at normal speed (typical vibration):
Fans at highest speed: