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Hi All,
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<div class="">We currently have what I believe is a fairly typical setup \u2026 metadata for our GPFS filesystems is the only thing in the system pool and it\u2019s on SSD, while data is on spinning disk (RAID 6 LUNs). Everything connected via 8 Gb FC SAN. 8 NSD servers.
Roughly 1 PB usable space.</div>
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<div class="">Now lets just say that you have a little bit of money to spend. Your I/O demands aren\u2019t great - in fact, they\u2019re way on the low end \u2026 typical (cumulative) usage is 200 - 600 MB/sec read, less than that for writes. But while GPFS has always been
great and therefore you don\u2019t need to Make GPFS Great Again, you do want to provide your users with the best possible environment.</div>
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<div class="">So you\u2019re considering the purchase of a dual-controller FC storage array with 12 or so 1.8 TB SSD\u2019s in it, with the idea being that that storage would be in its\u2019 own storage pool and that pool would be the default location for I/O for your main
filesystem \u2026 at least for smaller files. You intend to use mmapplypolicy nightly to move data to / from this pool and the spinning disk pools.</div>
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<div class="">Given all that \u2026 would you configure those disks as 6 RAID 1 mirrors and have 6 different primary NSD servers or would it be feasible to configure one big RAID 6 LUN? I\u2019m thinking the latter is not a good idea as there could only be one primary
NSD server for that one LUN, but given that: 1) I have no experience with this, and 2) I have been wrong once or twice before (<grin>), I\u2019m looking for advice. Thanks!</div>
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<div class="">\u2014</div>
<div class="">Kevin Buterbaugh - Senior System Administrator</div>
<div class="">Vanderbilt University - Advanced Computing Center for Research and Education</div>
<div class=""><a href="mailto:Kevin.Buterbaugh@vanderbilt.edu" class="">Kevin.Buterbaugh@vanderbilt.edu</a> - (615)875-9633</div>
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