elek commented on a change in pull request #1269: URL: https://github.com/apache/hadoop-ozone/pull/1269#discussion_r467072858
########## File path: hadoop-hdds/docs/content/concept/StorageContainerManager.md ########## @@ -0,0 +1,104 @@ +--- +title: "Storage Container Manager" +date: "2017-09-14" +weight: 3 +menu: + main: + parent: Architecture +summary: Storage Container Manager or SCM is the core metadata service of Ozone. SCM provides a distributed block layer for Ozone. +--- +<!--- + Licensed to the Apache Software Foundation (ASF) under one or more + contributor license agreements. See the NOTICE file distributed with + this work for additional information regarding copyright ownership. + The ASF licenses this file to You under the Apache License, Version 2.0 + (the "License"); you may not use this file except in compliance with + the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +--> + +Storage Container Manager (SCM) is the leader node of the *block space management*. The main responsibility is to create and manage [containers]({{<ref "concept/Containers.md">}}) which is the main replication unit of Ozone. + + + + +## Main responsibilities + +Storage container manager provides multiple critical functions for the Ozone +cluster. SCM acts as the cluster manager, Certificate authority, Block +manager and the Replica manager. + +SCM is in charge of creating an Ozone cluster. When an SCM is booted up via `init` command, SCM creates the cluster identity and root certificates needed for the SCM certificate authority. SCM manages the life cycle of a data node in the cluster. + + 1. SCM is the block manager. SCM +allocates blocks and assigns them to data nodes. Clients +read and write these blocks directly. + + 2. SCM keeps track of all the block +replicas. If there is a loss of data node or a disk, SCM +detects it and instructs data nodes make copies of the +missing blocks to ensure high availability. + + 3. **SCM's Ceritificate authority** is in +charge of issuing identity certificates for each and every +service in the cluster. This certificate infrastructure makes +it easy to enable mTLS at network layer and the block +token infrastructure depends on this certificate infrastructure. + +## Main components + +For a detailed view of Storage Container Manager this section gives a quick overview about the provided network services and the stored persisted data. + +**Network services provided by Storage Container Manager:** Review comment: Thanks a lot. I added the warning where the original page is updated and created jira issues for missing translations (for the new pages: (HDDS-4079,.....) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: ozone-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: ozone-issues-h...@hadoop.apache.org
