All Resource Manager data is stored on the Control Center master host. The Resource Manager application, running on delegate hosts, accesses the data through the distributed file system, which is based on NFS.
Using hypervisor commands alone to pause or stop Resource Manager virtual machines is unsupported. Resource Manager relies on timestamps and the system clock to keep services in sync, and pausing or stopping a virtual machine by using a hypervisor command disrupts the synchronization. Zenoss recommends the following procedure for pausing or stopping Resource Manager virtual machines:
- Log in to the Control Center browser interface.
- Stop Resource Manager.
- Use a hypervisor feature to shut down the virtual machine, or log in to the virtual machine as root and enter a shutdown command.
Similarly, vSphere vMotion is not supported unless all of the virtual machines in your Resource Manager deployment are paused or stopped.
vSphere hosts that run Control Center guest systems must be configured to synchronize their clocks with public or private NTP servers. Control Center guest systems synchronize their clocks with their vSphere hosts through an hourly invocation of VMware Tools. For more information about configuring a vSphere host for NTP, refer to your VMware documentation.
Multi-host deployments of Resource Manager running on Hyper-V hosts must be configured to synchronize their clocks with public or private NTP servers. The Resource Manager Installation Guide includes instructions for configuring NTP on Control Center guest systems. Hyper-V hosts do not provide the equivalent of VMware Tools so that guest systems can synchronize with the host.
Control Center includes backup and restore features for archiving and restoring Resource Manager data. The best practice is to use third party backup tools to archive the backup file.
Hypervisor backups can only be used instead of Control Center backups when Resource Manager, Control Center, and the Control Center master host are shut down cleanly and completely. Do not rely on hypervisor backups otherwise.