The cloud-provider-azure module is responsible for interacting with the Azure cloud resources. It allows the node manager module to use Azure resources for provisioning nodes for the defined node group (a group of nodes that are acted upon as if they were a single entity).

The cloud-provider-azure module:

  • Manages Azure resources using the cloud-controller-manager (CCM) module:
    • The CCM module creates network routes for the PodNetwork network on the Azure side;
    • The CCM module creates LoadBalancers for Kubernetes Service objects that have the LoadBalancer type;
    • The CCM module updates the metadata of the cluster nodes according to the configuration parameters and deletes nodes that are no longer in Azure;
  • Provisions nodes in Azure using the CSI storage component;
  • Enables the necessary CNI plugin (using the simple bridge);
  • Registers with the node-manager module so that AzureInstanceClasses can be used when creating the NodeGroup.

Note! When using load balancers, outgoing traffic also goes through it. If no balancer has UDP rules, all outgoing UDP traffic is blocked. As a result, such utilities as ntpdate and chrony do not work. To solve the problem, you need to add a load balancing rule with any UDP port to an existing balancer yourself, or create a service in the cluster with the LoadBalancer type with any UDP port.