<div dir="ltr"><div class="gmail_quote"><div dir="ltr">On Wed, Jul 1, 2015 at 6:57 PM Raj Wurttemberg <<a href="mailto:rajaw@c64.us">rajaw@c64.us</a>> wrote:</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I'm building a four-node cluster but I am unsure of what cluster software I<br>
should use. I will have NFS storage for a quorum if needed.<br></blockquote><div><br></div><div>It depends a lot on why you find this interesting. When I mess with this, I'm generally interested in fault tolerance as well as the potential to scale out an application.</div><div><br></div><div>So I noticed that there are two really important primitives for building fault-tolerant distributed systems. You don't always need both, but knowing what they are helps in designing systems.</div><div><br></div><div> * Consensus - Here the whole cluster appears to have a single, shared view about some fact.</div><div><br></div><div> * Eventual consistency - Here the cluster generally agrees, or will soon.</div><div><br></div><div>There are two easy to use and fault-tolerant high-level technologies that work on Raspberry Pi.</div><div><br></div><div> * etcd for consensus</div><div> <a href="https://github.com/coreos/etcd/blob/master/README.md">https://github.com/coreos/etcd/blob/master/README.md</a></div><div><br></div><div> * serf for gossip</div><div> <a href="https://www.serfdom.io/">https://www.serfdom.io/</a> </div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
NICs... Would I need a USB NIC for the cluster communication?<br></blockquote><div><br></div><div>I didn't:</div><div><br></div><div> <a href="https://edcashin.wordpress.com/2013/12/29/trying-etcd-on-android-mac-and-raspberry-pi/">https://edcashin.wordpress.com/2013/12/29/trying-etcd-on-android-mac-and-raspberry-pi/</a></div><div><br></div><div>... but it probably depends on your motivation and interests. <a href="http://mail.ale.org/mailman/listinfo" rel="noreferrer" target="_blank"></a><br>
</div><div><br></div><div>Please share your experiences, anyway. It sounds interesting.</div><div><br></div></div></div>