New features that affect upgrades from release 1.2.x

This release includes new features and new requirements that affect the upgrade process. The following list provides an overview of the changes that are addressed during this upgrade.

  • When storage becomes critically low, Control Center initiates an emergency shutdown of applications and services while sufficient resources remain to take action to avoid data loss. Support for this feature requires specific minimum amounts of space in the Control Center thin pool for application data.
  • This release replaces Docker 1.12.1 with Docker Community Edition (CE) 17.03.1. The upgrade instructions include steps to remove the yum repository description for Docker and replace it with the repository description for Docker CE.
  • The following new configuration variables are available in /etc/default/serviced, for tuning TCP/IP communications between ZooKeeper ensemble hosts and Control Center:
    • SERVICED_ZK_CONNECT_TIMEOUT
    • SERVICED_ZK_PER_HOST_CONNECT_DELAY
    • SERVICED_ZK_RECONNECT_START_DELAY
    • SERVICED_ZK_RECONNECT_MAX_DELAY
    For more information, see Control Center configuration file.
  • The Control Center RPM package includes a script that adds the serviced user group to a host, if necessary. Users must be members of the serviced group to use the command-line interface. For more information, see User access control.

For more information about this release, refer to the Control Center Release Notes.