use min instances 2 everywhere and update reference docs

charts/postgres-operator/crds/operatorconfigurations.yaml

@@ -341,7 +341,8 @@ spec:
                   #default: "transaction"
                 connection_pool_number_of_instances:
                   type: integer
-                  #default: 1
+                  minimum: 2
+                  #default: 2
                 connection_pool_default_cpu_limit:
                   type: string
                   pattern: '^(\d+m|\d+(\.\d{1,3})?)$'

charts/postgres-operator/crds/postgresqls.yaml

@@ -120,7 +120,7 @@ spec:
                     - "transaction"
                 numberOfInstances:
                   type: integer
-                  minimum: 1
+                  minimum: 2
                 resources:
                   type: object
                   required:

charts/postgres-operator/values.yaml

@@ -258,7 +258,7 @@ configConnectionPool:
   # default pooling mode
   connection_pool_mode: "transaction"
   # number of pooler instances
-  connection_pool_number_of_instances: 1
+  connection_pool_number_of_instances: 2
   # default resources
   connection_pool_default_cpu_request: "1"
   connection_pool_default_memory_request: "100Mi"

docs/reference/operator_parameters.md

@@ -604,25 +604,29 @@ but do not specify some of the parameters. All of them are optional with the
 operator being able to provide some reasonable defaults.
 
 * **connection_pool_number_of_instances**
-  How many instances of connection pool to create.
+  How many instances of connection pool to create. Default is 2 which is also
+  the required minimum.
 
 * **connection_pool_schema**
-  Schema to create for credentials lookup function.
+  Schema to create for credentials lookup function. Default is `pooler`.
 
 * **connection_pool_user**
   User to create for connection pool to be able to connect to a database.
+  Default is `pooler`.
 
 * **connection_pool_image**
   Docker image to use for connection pool deployment.
+  Default: "registry.opensource.zalan.do/acid/pgbouncer:master-5"
 
 * **connection_pool_max_db_connections**
-  How many connections the pooler can max hold.
+  How many connections the pooler can max hold. Default is 60.
 
 * **connection_pool_mode**
-  Default pool mode, session or transaction.
+  Default pool mode, `session` or `transaction`. Default is `transaction`.
 
 * **connection_pool_default_cpu_request**
   **connection_pool_default_memory_reques**
   **connection_pool_default_cpu_limit**
   **connection_pool_default_memory_limit**
-  Default resource configuration for connection pool deployment.
+  Default resource configuration for connection pool deployment. The internal
+  default for memory limit and request is `100Mi`, for CPU it is `1`.

manifests/configmap.yaml

@@ -18,7 +18,7 @@ data:
   connection_pool_image: "registry.opensource.zalan.do/acid/pgbouncer:master-5"
   # connection_pool_max_db_connections: 60
   # connection_pool_mode: "transaction"
-  # connection_pool_number_of_instances: 1
+  # connection_pool_number_of_instances: 2
   # connection_pool_schema: "pooler"
   # connection_pool_user: "pooler"
   # custom_service_annotations: "keyx:valuez,keya:valuea"

manifests/operatorconfiguration.crd.yaml

@@ -317,7 +317,8 @@ spec:
                   #default: "transaction"
                 connection_pool_number_of_instances:
                   type: integer
-                  #default: 1
+                  minimum: 2,
+                  #default: 2
                 connection_pool_default_cpu_limit:
                   type: string
                   pattern: '^(\d+m|\d+(\.\d{1,3})?)$'

manifests/postgresql.crd.yaml

@@ -84,7 +84,7 @@ spec:
                     - "transaction"
                 numberOfInstances:
                   type: integer
-                  minimum: 1
+                  minimum: 2
                 resources:
                   type: object
                   required:

pkg/apis/acid.zalan.do/v1/crds.go

@@ -105,6 +105,7 @@ var OperatorConfigCRDResourceColumns = []apiextv1beta1.CustomResourceColumnDefin
 
 var min0 = 0.0
 var min1 = 1.0
+var min2 = 2.0
 var minDisable = -1.0
 
 // PostgresCRDResourceValidation to check applied manifest parameters
@@ -198,7 +199,7 @@ var PostgresCRDResourceValidation = apiextv1beta1.CustomResourceValidation{
 							},
 							"numberOfInstances": {
 								Type:    "integer",
-								Minimum: &min1,
+								Minimum: &min2,
 							},
 							"resources": {
 								Type:     "object",
@@ -491,7 +492,7 @@ var PostgresCRDResourceValidation = apiextv1beta1.CustomResourceValidation{
 						Type: "string",
 					},
 					"tls": {
-						Type: "object",
+						Type:     "object",
 						Required: []string{"secretName"},
 						Properties: map[string]apiextv1beta1.JSONSchemaProps{
 							"secretName": {
@@ -1166,7 +1167,7 @@ var OperatorConfigCRDResourceValidation = apiextv1beta1.CustomResourceValidation
 							},
 							"connection_pool_number_of_instances": {
 								Type:    "integer",
-								Minimum: &min1,
+								Minimum: &min2,
 							},
 							"connection_pool_schema": {
 								Type: "string",