Glusterfs Kubernetes Cluster Sidecar

This project is as a PoC to setup a gluster cluster using Kubernetes. It should handle resizing of any type and be resilient to the various conditions both gluster and kubernetes can find themselves in.

How to use it

There is an article here explaining how to use this here: https://medium.com/@jaime_ecom/glusterfs-cluster-with-kubernetes-c09725d69900#.18m72xv4k

The docker image is hosted on docker hub and can be found here:
https://hub.docker.com/r/neshte/gluster-k8s-sidecar/

An example kubernetes replication controller can be found in the examples directory on github here:
https://github.com/neshte/gluster-k8s-sidecar

There you will also find some helper scripts to test out creating the cluster and resizing it.

Settings

• GLUSTER_SIDECAR_POD_LABELS
  Required: NO
  Default: role=gluster,environment=test
  This should be a be a comma separated list of key values the same as the podTemplate labels. See above for example.
• GLUSTER_SIDECAR_SLEEP_SECONDS
  Required: NO
  Default: 5
  This is how long to sleep between work cycles.
• GLUSTER_SIDECAR_UNHEALTHY_SECONDS
  Required: NO
  Default: 15
  This is how many seconds a cluster member has to get healthy before automatically being removed from the cluster.
• GLUSTER_SIDECAR_CLUSTER_NAME
  Required: NO
  Default: glusterfs-cluster
  This is the meta.name of the kubernetes endpoints.
• GLUSTER_SIDECAR_CLUSTER_PORT
  Required: NO
  Default: 1
  This is the cluster port for kubernetes gluster volume mounting.
• GLUSTER_SIDECAR_VOLUME_NAME
  Required: NO
  Default: data
  This is the gluster volume name.
• GLUSTER_SIDECAR_BRICK_NAME
  Required: NO
  Default: data
  This is the gluster brick name.
• GLUSTER_SIDECAR_REPLICATION
  Required: NO
  Default: 2
  This is the replication factor for files on gluster cluster.
• GLUSTER_SIDECAR_K8SNAMESPACE
  Required: NO
  Default: default
  This is the namespace in which this sidecar will run.

Debugging

If you follow the instructions on article: https://medium.com/@jaime_ecom/glusterfs-cluster-with-kubernetes-c09725d69900#.18m72xv4k

On the sidecar of the first node you create, you will see your logs for debugging

Still to do

• Test performance of gluster (with more than 100 nodes or something like that)
• Test real cases of failure and autorecovery
• Allow to add/remove any pod number, not just the last one
• Add support for fully distributed non-replicated cluster
• Parametrize also on Makefile to avoid the need to change the rc-template and svc-template manually
• Add tests!
• Add to circleCi

Inspired in

This sidecar is inspired in a sidecar for mongo on kubernetes https://github.com/leportlabs/mongo-k8s-sidecar