New features

Control Center 1.3.3 replaces Docker 1.12.1 with Docker Community Edition (CE) 17.03.1. The following new configuration variables are available in /etc/default/serviced for tuning TCP/IP communications between ZooKeeper ensemble hosts and Control Center:
For information about removing the old version of Docker and installing the new, refer to the Control Center Upgrade Guide.

Before upgrading to Control Center 1.3.3, you must ensure you have sufficient free space in both the thin pool metadata volume and the thin pool data volume. The thin pool metadata volume should be at least 1% of the size of the thin pool data volume (if created by an earlier version of serviced-storage, it may be smaller). In addition, you must have at least 3GB of available space in the thin pool data volume because this is the minimum buffer before an emergency shutdown will commence. If less than 3GB is available, you must provision additional storage or serviced will fail to start after the upgrade.

Refer to the Control Center Upgrade Guide for details.