Infrastructure nodes disk layout¶

Infrastructure nodes are typically installed on hardware servers. These servers run all components of management and control plane for both MCP and the cloud itself. It is very important to configure hardware servers properly upfront because changing their configuration after initial deployment is costly.

For instructions on how to configure the disk layout for MAAS to provision the hardware machines, see MCP Deployment Guide: Add a custom disk layout per node in the MCP model.

Consider the following recommendations:

Layout

Mirantis recommends using the LVM layout for disks on infrastructure nodes. This option allows for more operational flexibility, such as resizing the Volume Groups and Logical Volumes for scale-out.

LVM Volume Groups

According to Hardware requirements for Cloud Provider Infrastructure, an infrastructure node typically has two or more SSD disks. These disks must be configured as LVM Physical Volumes and joined into a Volume Group.

The name of the Volume Group is the same across all infrastructure nodes to ensure consistency of LCM operations. Mirantis recommends following the vg_<role> naming convention for the Volume Group. For example, vg_root.

LVM Logical Volumes

The following table summarizes the recommended Logical Volume schema for infrastructure nodes in the CPI reference architecture. The /var/lib/libvirt/images/ size may be adjusted to the size of all VMs hosted on the node depending on the VCP VMs size. The disk size for a large deployment may require more that 3 TB for StackLight LMA and OpenContrail.

Follow the instructions in the MCP Deployment Guide to configure infrastructure nodes in your cluster model.