Install and Configure a Cassandra Database for Storing Historic Metric Data

VMware Cloud Director can collect metrics that provide current and historic information about virtual machine performance and resource consumption for the virtual machines that are in your cloud. Data for historic metrics is stored in a Cassandra cluster.

Cassandra is an open-source database that you can use to provide the backing store for a scalable, high-performance solution for collecting time series data like virtual machine metrics. If you want VMware Cloud Director to support retrieval of historic metrics from virtual machines, you must install and configure a Cassandra cluster, and use the cell-management-tool to connect the cluster to VMware Cloud Director. Retrieval of current metrics does not require optional database software.

Prerequisites

• Verify that VMware Cloud Director is installed and running before you configure the optional database software.
• If you are not already familiar with Cassandra, review the material at http://cassandra.apache.org/.
• See the VMware Cloud Director Release Notes for a list of Cassandra releases supported for use as a metrics database. You can download Cassandra from http://cassandra.apache.org/download/.
• Install and configure the Cassandra cluster :
  • The Cassandra cluster must include least four virtual machines deployed on two or more hosts.
  • Two Cassandra seed nodes are required.
  • Enable Cassandra client-to-node encryption. See http://docs.datastax.com/en/cassandra/3.0/cassandra/configuration/secureSSLIntro.html.
  • Enable Cassandra user authentication. See http://docs.datastax.com/en/cassandra/3.0/cassandra/configuration/secureConfigNativeAuth.html.
  • Enable Java Native Access (JNA) version 3.2.7 or later on each Cassandra cluster.
  • Cassandra node-to-node encryption is optional.
  • Use of SSL with Cassandra is optional. If you decide not to enable SSL for Cassandra, you must set the configuration parameter cassandra.use.ssl to 0 in the global.properties file on each cell ($VCLOUD_HOME/etc/global.properties)

Procedure

1. Use the cell-management-tool utility to configure a connection between VMware Cloud Director and the nodes in the Cassandra cluster.
   In the following example command, node1-ip, node2-ip, node3-ip, and node4-ip are the IP address of the members of the Cassandra cluster. The default port (9042) is used. Metrics data is retained for 15 days.

   [root@cell1 /opt/vmware/vcloud-director/bin]# ./cell-management-tool cassandra --configure --create-schema \
   --cluster-nodes node1-ip,node2-ip,node3-ip, node4-ip \
   --username admin --password 'P@55w0rd' --ttl 15

   For information about using the cell management tool, see Cell Management Tool Reference.
2. (Optional) If you are upgrading VMware Cloud Director from version 9.1, use the cell-management-tool to configure the metrics database to store rolled-up metrics.
   Run a command similar to the following example:

   [root@cell1 /opt/vmware/vcloud-director/bin]# ./cell-management-tool cassandra --add-rollup \
   --username admin --password 'P@55w0rd'

3. Restart each VMware Cloud Director cell.