From 4689c21cb46ded08929c7d43270633f5e4714016 Mon Sep 17 00:00:00 2001
From: Pawan <pawan@mayadata.io>
Date: Tue, 31 Dec 2019 16:54:50 +0530
Subject: [PATCH] feat(HA): adding support to have controller in HA

We can have more than one controller in the system, but only one will
be the master and others will be slave. Once master is down, one of the slave will
take over via lease mechanism and start provisioning/deprovisioning the volumes.

Signed-off-by: Pawan <pawan@mayadata.io>
---
 deploy/zfs-operator.yaml | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/deploy/zfs-operator.yaml b/deploy/zfs-operator.yaml
index 75aee0a8..0c486300 100644
--- a/deploy/zfs-operator.yaml
+++ b/deploy/zfs-operator.yaml
@@ -82,6 +82,9 @@ rules:
   - apiGroups: [""]
     resources: ["events"]
     verbs: ["list", "watch", "create", "update", "patch"]
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "watch", "list", "delete", "update", "create"]
   - apiGroups: ["*"]
     resources: ["zfsvolumes"]
     verbs: ["*"]
@@ -112,7 +115,7 @@ spec:
       app: openebs-zfs-controller
       role: openebs-zfs
   serviceName: "openebs-zfs"
-  replicas: 1
+  replicas: 2
   template:
     metadata:
       labels:
@@ -130,6 +133,8 @@ spec:
             - "--v=5"
             - "--feature-gates=Topology=true"
             - "--strict-topology"
+            - "--enable-leader-election"
+            - "--leader-election-type=leases"
           env:
             - name: ADDRESS
               value: /var/lib/csi/sockets/pluginproxy/csi.sock
@@ -142,6 +147,7 @@ spec:
           args:
             - "--v=5"
             - "--csi-address=$(ADDRESS)"
+            - "--leader-election"
           env:
             - name: ADDRESS
               value: /var/lib/csi/sockets/pluginproxy/csi.sock
@@ -201,7 +207,9 @@ rules:
   - apiGroups: ["storage.k8s.io"]
     resources: ["volumeattachments", "csinodes"]
     verbs: ["get", "list", "watch", "update", "patch"]
-
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "watch", "list", "delete", "update", "create"]
 ---
 kind: ClusterRoleBinding
 apiVersion: rbac.authorization.k8s.io/v1