Cloudera Docs

Step 3: Before You Upgrade the Operating System

Loading Filters ... 6.3.4 6.3.3 6.3.1 6.3.0 6.2.1 6.2.0 6.1.1 6.1.0 6.0.1 6.0.0 7.11.3 7.7.3 7.7.1 7.6.7 7.6.1 7.4.4 6.3.4 6.3.3 6.3.2 6.3.1 6.3.0 6.2.1 6.2.0 6.1.1 6.1.0 6.0.2 6.0.1 7.1.9.1000 7.1.9 7.1.8 7.1.7.3000 7.1.7.2000 7.1.7.1000 7.1.7

This topic describes steps you must perform before upgrading the operating system on a host managed by Cloudera Manager.

Decommission and Stop Running Roles

  1. Log in to the Cloudera Manager Admin Console.
  2. From the All Hosts page, select the host that you wish to upgrade. Cloudera recommends that you upgrade only one host at a time.
  3. Select Begin Maintenance (Suppress Alerts/Decommission) from the Actions menu.
  4. Select Host Decommission from the Actions menu. Any roles that do not require decommission will be skipped.
  5. If the operating system upgrade procedure takes less than 30 minutes per node, you do not need to decommission the DataNode.

    If the Cloudera Manager and CDH/ version are both 5.14 or greater, you can also choose the Take DataNode Offline feature.

    If in doubt, decommission the roles.

    • When a DataNode is decommissioned, the NameNode ensures that every block from the DataNode is still available across the cluster as specified by the replication factor. This procedure involves copying blocks off the DataNode in small batches. In cases where a DataNode has several thousand blocks, decommissioning takes several hours.
    • When a DataNode is turned off without being decommissioned:
      • The NameNode marks the DataNode as dead after a default of 10m 30s (controlled by the dfs.heartbeat.interval and dfs.heartbeat.recheck.interval configuration properties).
      • The NameNode schedules the missing replicas to be placed on other DataNodes.
      • When the DataNode comes back online and reports to the NameNode, the NameNode schedules blocks to be copied to it while other nodes are decommissioned or when new files are written to HDFS.
    • You can also speed up the decommissioning of a DataNode by increasing values for these properties:
      • dfs.max-repl-streams: The number of simultaneous streams used to copy data.
      • dfs.balance.bandwidthPerSec: The maximum amount of bandwidth that each DataNode can utilize for balancing, in bytes per second.
      • dfs.namenode.replication.work.multiplier.per.iteration: NameNode configuration requiring a restart, defaults to 2 but can be raised to 10 or higher.

        This determines the total amount of block transfers to begin in parallel at a DataNode for replication, when such a command list is being sent over a DataNode heartbeat by the NameNode. The actual number is obtained by multiplying this value by the total number of live nodes in the cluster. The result number is the number of blocks to transfer immediately, per DataNode heartbeat.

  6. Once that is completed, select the same host again and choose Stop Roles on Hosts.

Stop Cloudera Manager Agent

  1. Hard Stop the Cloudera Manager Agent.
    RHEL 7, SLES 12, Ubuntu 18.04 and higher
    sudo systemctl stop cloudera-scm-supervisord.service
    RHEL 5 or 6, SLES 11, Debian 6 or 7, Ubuntu 12.04 or 14.04
    
sudo service cloudera-scm-agent hard_stop

Stop Cloudera Manager Server & Agent

  1. Hard Stop the Cloudera Manager Agent.
    RHEL 7, SLES 12, Ubuntu 18.04 and higher
    sudo systemctl stop cloudera-scm-supervisord.service
    RHEL 5 or 6, SLES 11, Debian 6 or 7, Ubuntu 12.04 or 14.04
    
sudo service cloudera-scm-agent hard_stop
  2. Stop the Cloudera Management Service.
    1. Log in to the Cloudera Manager Admin Console.
    2. Select Clusters > Cloudera Management Service.
    3. Select Actions > Stop.
  3. Stop the Cloudera Manager Server.
    sudo systemctl stop cloudera-scm-server

Stop Databases

  1. If you are using the embedded PostgreSQL database, stop the Cloudera Manager Embedded PostgreSQL database:
    RHEL 7, SLES 12, Ubuntu 18.04 and higher
    sudo systemctl stop cloudera-scm-server-db
    RHEL 5 or 6, SLES 11, Debian 6 or 7, Ubuntu 12.04 or 14.04
    sudo service cloudera-scm-server-db stop

    If you are not using the embedded PostgreSQL database and you attempt to stop it, you might see a message indicating that the service cannot be found. If you see a message that the shutdown failed, then the embedded database is still running, probably because services are connected to the Hive metastore. If the database shutdown fails due to connected services, issue the following command:

    RHEL-compatible 7 and higher, Ubuntu 16.04
    sudo service cloudera-scm-server-db next_stop_fast
sudo service cloudera-scm-server-db stop
    All other Linux distributions
    sudo service cloudera-scm-server-db fast_stop
  2. If there are other database servers running on this host, they must be stopped also.

Remove Packages & Parcels

Packages for the older operating system won’t be able to start on the new operating system. Remove old packages from the host.

  1. RHEL / CentOS
    sudo yum remove cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2
    SLES
    sudo zypper remove cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2
    Ubuntu
    sudo apt-get purge cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2
  2. RHEL / CentOS
    sudo yum remove cloudera-manager-server cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2
    SLES
    sudo zypper remove cloudera-manager-server cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2
    Ubuntu
    sudo apt-get purge cloudera-manager-server cloudera-manager-daemons cloudera-manager-agent cloudera-manager-server-db-2

  3. Remove old CDH parcels from the host. These are built for your old operating system.

    The Cloudera Manager agent will download and activate the proper parcel for the new operating system when it is started.

    Empty the contents of the following directories. These are the defaults for parcel storage - if you use other directories, please change accordingly.

    sudo rm -rf /opt/cloudera/parcels/*
    sudo rm -rf /opt/cloudera/parcel-cache/*

Upgrade the Operating System

Use the operating system upgrade procedures provided by your operating system vendor (for example: RedHat or Ubuntu) to download their software and perform the operating system upgrade.