<div dir="ltr">Thanks, <div><br></div><div>The 3 servers are new Lenovo units with redundant PS backed by two huge UPS units (on for each bank of power supplies). I think the chances of losing two nodes is incredibly slim, and in that case a Disaster Recovery from offsite backups would be reasonable.</div><div><br></div><div>My requirements are about 2TB, highly available (so that I can reboot one of the 3 servers without taking down services). </div><div><br></div><div>Beyond that my focus is high performance for small I/O. </div><div><br></div><div>So I could do a single 2TB SSD per server, or two, or many more if that is "what is required". But I don't want to waste money...</div><div><br></div><div>I like the idea of forgoing the RAID cards as they are quite expensive, especially the capacitor backed ones. The onboard controller can handle JBOD just fine, if Gluster is OK with it!</div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div><div dir="ltr" style="font-size:12.8px"><font size="4" face="arial narrow, sans-serif"><b>Vincent Royer</b></font></div><div dir="ltr"><div style="font-size:12.8px"><font size="4" face="arial narrow, sans-serif"><b>778-825-1057</b></font></div><div style="font-size:12.8px"><font size="4" face="arial narrow, sans-serif"><b><br></b></font></div><div style="font-size:12.8px"><a href="http://www.epicenergy.ca/" target="_blank"><img src="https://lh3.googleusercontent.com/ezD9JxeN67lTscselHjW4ZEqvQRj_i_T_Ky_s__GkR0AtanG1nK52CD1Rdhmyzbk7XRPf-Rhhnr2-SLPmhtd0J8xVMp0xOiR20ebQVb6jU2xwJPKN4lePRq5G2p93ybqA4SnqjCWCvEsNlK37a9FtStdFcTJyIoS2aHKiL69L3bZg1g7mEAMr7IHXVYvHgq3MX9rNaqIQx9T3uPuIHEDIfxrgpCrsBoEamgaRHj5hcpEobnogqCqpa1sRcKy927TSeR5BbVLM1-wn0h-4LvE8CMqj30jpQULxZ9uXEg_S6sR3ZeZjtkkRvgK4l_wiivWlyV_SjCDQ5QREG3jkuCjXC04i1NNmziGZZNWYsaohE6khrN4JGVtvaSOiS2woYJNz3Gt0EucxJp3eUBYspzTl9iZia7bLvFEGIODvmfjRVZJmnCrFucJxGkAtWn_EUIbxJXS5NWAFnvBoixQP563Fbu7dFKL77lDcb4PHwrnJVjqcgU0OTeiMBlMvEt97YgMpMvdi7rx9L4DeEbrIGUovgx4QLfRRoF_9u2mxFu8FHupCxfocSyB3vs8gqOLvVdx42qwiLN0sGLAg8K3G_vFwVNddXQ_yb3cGeCEAOTnk7jfiP4O4jsPIW2RRbnKKL-usL11Tp7gkxbgRouLOoyqpbisjA4vRWDeylj1yDGyBg=w400-h38-no" width="200" height="18"><br></a></div><div><b><font face="arial narrow, sans-serif" size="2">SUSTAINABLE MOBILE <font color="#6aa84f">ENERGY </font>SOLUTIONS</font></b></div></div></div><div><br></div><div><br><div><div><br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
<br><div class="gmail_quote">On Mon, Apr 9, 2018 at 11:25 AM, Alex Crow <span dir="ltr"><<a href="mailto:acrow@integrafin.co.uk" target="_blank">acrow@integrafin.co.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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On 09/04/18 19:02, Vincent Royer wrote:<br>
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<div>Thanks, </div>
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<div>I suppose what I'm trying to gain is some
clarity on what choice is best for a given
application. How do I know if it's better
for me to use a raid card or not, to include
flash-cache on it or not, to use ZFS or not,
when combined with a small number of SSDs in
Replica 3. </div>
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How few is "small number" - most importantly number per server?
Replica 3 is a start, as it already tells us you can lose at one
entire server and carry on as normal. If you lose two, your
GlusterFS is down.<br>
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What is your resilience goal? You should really be starting with
requirements, not speccing out and buying servers and drives and
then trying to force them to fit your expectations.<span class=""><br>
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