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Looking at the defaults for Kubernetes on GCE and AWS, it looks like even for very large clusters (hundredes hundreds of nodes), they use a single Master node – only the machine size changes. There is no mention of installing etcd on a separate server, although they do install a separate etcd for events. The default compute node size is n1-standard-2 (2 VCPU, 8 GB RAM).
The Gluster documentation suggests a minimum of 2 servers.
For testing NDS Labs, we can setup a small cluster:
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http://kubernetes.io/docs/admin/high-availability/
https://coreos.com/blog/improving-kubernetes-scheduler-performance.html – mentions "separate etcd cluster"
Gluster
http://www.gluster.org/community/documentation/index.php/QuickStart
"Have at least two nodes"
Failover
Even though the client appears to be mounting from a single server, apparently the client is smart enough to get information about available peers during mount.
Performance monitoring
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