Add a Managed Cluster node

  • How-to guide
  • 3-min read

You can scale your Managed Cluster by adding nodes through the Cluster Management Console. You need root access to the target host to run the installer.

Step 1

Download installer

Step 2

Run installer

Step 3

Finalize

  • You cannot add additional cluster nodes until synchronization completes.
  • After removing a cluster node, wait 72 hours before installing a new node on a host with the same IP address (for example, when reinstalling on the same host).

Step 1 Download installer

  1. Log in to the Cluster Management Console.

  2. Go to Deployment Status and select Add new cluster node.

  3. Copy the wget command line from the Run this command on the target host text field and paste it into your terminal window. Wait for the download to complete.

Step 2 Run installer

  1. Run one of the following commands from the directory where you downloaded the installation script. Root access is required.

    Replace <version> with your Dynatrace Managed version.

    • Ubuntu Server

      sudo /bin/sh dynatrace-managed-<version>.sh

    • Red Hat Enterprise Linux

      su -c '/bin/sh dynatrace-managed-<version>.sh'

    • Other Linux distributions with root session

      /bin/sh dynatrace-managed-<version>.sh

  2. Type Accept to agree to the Dynatrace Managed Terms of use. Installation will not continue until you complete this step. To quit installation, press Ctrl+C.

  3. Accept the prompts for values such as installation path and user account by pressing Enter. To override a value, type your choice and press Enter.

Step 3 Finalize

The newly added node appears in the Cluster Management Console with the status joining during installation. Full data synchronization can take a couple of hours. To monitor cluster node synchronization progress, run:

[root@host]# /opt/dynatrace-managed/utils/cassandra-nodetool.sh status

Example response:

Datacenter: datacenter-1
=====================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address        Load       Tokens       Owns (effective)  Host ID                               Rack
UN  1.6.1.6  349.88 GiB       256          100.0%            aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee  rack1
UN  1.6.2.2  358.2 GiB        256          100.0%            zzzzzzzz-xxxx-cccc-vvvv-ffffffffffff  rack1
UJ  1.6.3.9  278.75 GiB       256          75.1%             qqqqqqqq-wwww-eeee-rrrr-rrrrrrrrrrrr  rack1

Where UJ marks the node as joining and the Owns (effective) column shows the progress of data synchronization.

How to read the response

A 100% result in the Owns (effective) column is correct only for clusters that have up to three nodes.

If there are more than three nodes, the percentage is calculated as follows:

3/(number_of_nodes)*100%

When you add more than three nodes, the percentage column changes as follows:

  • 4 nodes will show 75%
  • 5 nodes will show 60%
  • 6 nodes will show 50%

FAQ

Can I add a node using the Managed Cluster installation procedure?

Yes, you can add a node using the same procedure as for installing a Managed Cluster. The difference is that the installer asks whether to add the node to an existing cluster (you must enter the IP address of an existing cluster node) or set up a new cluster. Alternatively, use the --seed-auth parameter to skip this prompt and automatically add the node to the existing cluster.

Can I use a privilege management system other than sudo?

Yes, you can use pbrun, but you must grant the Dynatrace user permission to run /opt/dtrun/dtrun *. Specify the user who is installing Dynatrace Managed and the command that replaces sudo. Note that <version> represents the Dynatrace Managed version number.

/bin/sh dynatrace-managed-<version>.sh --system-user dynatrace:dynatrace --sudo-cmd  "/usr/bin/pbrun \$CMD"

For maintenance purposes, add the following script paths to your privilege management configuration:

  • /opt/dynatrace-managed/uninstall-dynatrace.sh
  • /opt/dynatrace-managed/launcher/*
  • /opt/dynatrace-managed/utils/*

Run this command to stop all Dynatrace Managed processes on a node:

pbrun /opt/dynatrace-managed/launcher/dynatrace.sh stop

Do not remove or overwrite dtrun, as it is required by installation and update procedures. The installer calls dtrun without arguments to validate that the user has administrative privileges, but for normal operation Dynatrace calls dtrun with arguments to actually run commands.