Updated Backup to Cloud (markdown)

Backup-to-Cloud.md

@@ -5,3 +5,51 @@ So you have the benefit of:
 * Extremely fast access to local SeaweedFS Filer
 * Near-Real-Time Backup to Amazon S3 with zero-cost upload network traffic.
 
+# Configuration
+* Configure notification. use "`weed scaffold -config=filer`" to see the notification section.
+
+```
+[notification.log]
+enabled = false
+
+[notification.kafka]
+enabled = true
+hosts = [
+  "localhost:9092"
+]
+topic = "seaweedfs_filer_to_s3"
+
+```
+
+* Setup Kafka. Possibly you need to create the Kafka topic if auto topic creation is not enabled.
+
+* Configure replication. use "`weed scaffold -config=replication`" to see the notification section.
+
+```
+[source.filer]
+enabled = true
+grpcAddress = "localhost:18888"
+directory = "/buckets"    # all files under this directory tree are replicated
+
+[notification.kafka]
+enabled = true
+hosts = [
+  "localhost:9092"
+]
+topic = "seaweedfs_filer_to_s3"
+
+[sink.s3]
+# read credentials doc at https://docs.aws.amazon.com/sdk-for-go/v1/developer-guide/sessions.html
+# default loads credentials from the shared credentials file (~/.aws/credentials).
+enabled = false
+aws_access_key_id     = ""     # if empty, loads from the shared credentials file (~/.aws/credentials).
+aws_secret_access_key = ""     # if empty, loads from the shared credentials file (~/.aws/credentials).
+region = "us-west-1"
+bucket = "your_bucket_name"    # an existing bucket
+directory = ""                 # destination directory (do not prefix or suffix with "/")
+
+```
+
+* Start the Kafka.
+* Start the replication. "`weed filer.replicate`"
+* Start the filer. "`weed filer`"