Codis-Operator

Codis Operator creates and manages codis clusters running in kubernetes.(Notice,It is not ready for production/Work In Progress)

Advantages based on k8s

NO SPOF RISK

Codis dashboard component which does migration/cluster management work is a spof, if it is deployed by traditional method and when it fails, we have to recover it manually,however,it will be self-healing based on k8s.

Easily Create/Maintain Cluster

Codis Cluster has a lots of components(proxy/dashboard/redis/fe/sentinel).it will cost a lot of time if it is deployed and managed by traditional method,especially when nodes die,cut off,we have to recover/migrate every component manually.however,we can easily deploy/destory cluster with only one command based on k8s,and when proxy/dashboard/fe fails(node die,outage,node cut,node resource exhaustion),all these failures will be self-healing that saves much time.

Feature

Create and Destroy Codis Cluster

Deploy/Destroy cluster with only one comannd

Scaling the Codis Cluster

Automatically scales the proxy component

Automatic FailOver

Automatically performs failover when proxy/dashboard/fe failed.

Automatically monitoring Codis Cluster

Automatically deploy Prometheus,Grafana for Codis cluster monitoring.

Getting Start(Demo)

OverView

Deploy Codis Operator

kubectl create -f ./deploy/manager/deployment-dev.yml

Create and destroy a codis cluster

kubectl create -f ./examples/sample-1.yml

kubectl delete -f ./examples/sample-1.yml

Best Practices

• specifying coordinator name to etcd/zookeeper

• use pv to store Redis data(ssd disk is better)

• use dedicated node to run codis-server(Redis)

• set max memory limit(node memory) for codis-server and assign enough memory

• make sure request resource and limit source are equal(k8s pod qos is guaranteed,evict/oom seldom happens)

• it is better that if your pod ip is sticky.

EXAMPLES

reference linking:

https://github.com/tangcong/codis-operator/blob/master/examples/sample-3.yml

• using network pv(specifying storageClassName)

• enabling hpa

• specifying service type

• specifying coordinator name

• specifying request/limit resource

• specifying scheduler policy(node selector/tolerations)

To do List

• monitor(proxy/redis)

• dedicated scheduler server(k8s do not know "codis group" conception, one group may have 2-N replicas, we want to make sure that every codis server pod which is in the same group be scheduled into different node, when one node crash/outage,we can promote other slave to master.)

• make sure that drain node safely and automatically.

• support helm

• support local pv

• add unit test

• add e2e test

• add chaos test

SNAPSHOTS