An OS Template has been registered on the virtualization node. How to define to which other existing nodes it will be the delivered?
TemplateDeliveryJob is responsible for OS Template delivery to virtualization nodes. This job is being executed by the Instance Manager server every 5 minutes or after the following events:
- new Virtualization Node is added to OACI;
- new OS Template is registered on the Virtualization Node;
- new VE based on OS Template is created.
During the job execution the following criteria are being checked to find suitable nodes:
- Node is in Active state;
- Virtualization Hardware Node Tags are suitable for Operating system properties of OS Template;
- Node belongs to the same location as the virtualization node where OS Template was originally installed;
- Node has
usage_index parameter is calculated depending on RAM, CPU, Bandwidth and Disk usages on Virtualization Hardware Node, representing node load in percents.
The value of
node-usage-threshold parameter is defined in
IM-config.xml file on Instance Manager server, by default is it 95:
# grep node-usage-threshold /usr/local/share/PACI-im/IM-config.xml <os-templates-proactive-delivery default-high-watermark="80" default-low-watermark="20" node-usage-threshold="95" />
In order to avoid virtualization nodes overload, it is not recommended to increase this threshold.
After the list of suitable nodes is obtained, the job calculates the amount of nodes to which OS Template has to be automatically distributed and installed. It depends on specified OS Template Registration Parameters
High Watermark (percentage). For example, if in result of aforementioned selection were chosen 10 suitable nodes,
High Watermark= 90, OS template will be installed to 9 nodes from the list - 90%.
Detailed description of these parameters can be found in the Cloud Infrastructure Integration Guide:
There are additional limitations on delivery:
Custom CT OS templates are not propagated automatically across the virtualization nodes in one location. It's required to manually copy them on the nodes with missing OS templates.
Custom VM OS templates, which were created manually on Virtuozzo node, are not propagated automatically between nodes. It's required to migrate them manually across the nodes. The hardware nodes should be in one location. For more details how to migrate custom VM OS templates between virtualization nodes in one location, refer to the following article:
#130011 Moving Custom VM OS Templates Between Virtualization Nodes in One Location.