Merge branch 'master' into feature/connection-pooler

docs/reference/cluster_manifest.md

@@ -392,3 +392,24 @@ present.
 
 * **resources**
   Resource configuration for connection pool deployment.
+
+## Custom TLS certificates
+
+Those parameters are grouped under the `tls` top-level key.
+
+* **secretName**
+  By setting the `secretName` value, the cluster will switch to load the given
+  Kubernetes Secret into the container as a volume and uses that as the
+  certificate instead. It is up to the user to create and manage the
+  Kubernetes Secret either by hand or using a tool like the CertManager
+  operator.
+
+* **certificateFile**
+  Filename of the certificate. Defaults to "tls.crt".
+
+* **privateKeyFile**
+  Filename of the private key. Defaults to "tls.key".
+
+* **caFile**
+  Optional filename to the CA certificate. Useful when the client connects
+  with `sslmode=verify-ca` or `sslmode=verify-full`.

docs/reference/operator_parameters.md

@@ -284,7 +284,7 @@ configuration they are grouped under the `kubernetes` key.
   used for AWS volume resizing and not required if you don't need that
   capability. The default is `false`.
 
- * **master_pod_move_timeout**
+* **master_pod_move_timeout**
    The period of time to wait for the success of migration of master pods from
    an unschedulable node. The migration includes Patroni switchovers to
    respective replicas on healthy nodes. The situation where master pods still
@@ -472,7 +472,7 @@ grouped under the `logical_backup` key.
   When using non-AWS S3 storage, endpoint can be set as a ENV variable. The default is empty.
 
 * **logical_backup_s3_sse**
-  Specify server side encription that S3 storage is using. If empty string
+  Specify server side encryption that S3 storage is using. If empty string
   is specified, no argument will be passed to `aws s3` command. Default: "AES256".
 
 * **logical_backup_s3_access_key_id**

docs/user.md

@@ -564,3 +564,50 @@ should be general approach between different implementation).
 Note, that using `pgbouncer` means meaningful resource CPU limit should be less
 than 1 core (there is a way to utilize more than one, but in K8S it's easier
 just to spin up more instances).
+
+## Custom TLS certificates
+
+By default, the spilo image generates its own TLS certificate during startup.
+This certificate is not secure since it cannot be verified and thus doesn't
+protect from active MITM attacks. In this section we show how a Kubernete
+Secret resources can be loaded with a custom TLS certificate.
+
+Before applying these changes, the operator must also be configured with the
+`spilo_fsgroup` set to the GID matching the postgres user group. If the value
+is not provided, the cluster will default to `103` which is the GID from the
+default spilo image.
+
+Upload the cert as a kubernetes secret:
+```sh
+kubectl create secret tls pg-tls \
+  --key pg-tls.key \
+  --cert pg-tls.crt
+```
+
+Or with a CA:
+```sh
+kubectl create secret generic pg-tls \
+  --from-file=tls.crt=server.crt \
+  --from-file=tls.key=server.key \
+  --from-file=ca.crt=ca.crt
+```
+
+Alternatively it is also possible to use
+[cert-manager](https://cert-manager.io/docs/) to generate these secrets.
+
+Then configure the postgres resource with the TLS secret:
+
+```yaml
+apiVersion: "acid.zalan.do/v1"
+kind: postgresql
+
+metadata:
+  name: acid-test-cluster
+spec:
+  tls:
+    secretName: "pg-tls"
+    caFile: "ca.crt" # add this if the secret is configured with a CA
+```
+
+Certificate rotation is handled in the spilo image which checks every 5
+minutes if the certificates have changed and reloads postgres accordingly.