Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Starting with MOSK 25.2, the MOSK documentation set covers all product layers, including MOSK management (formerly MCC). This means everything you need is in one place. The separate MCC documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

Migration limitations and impact

This section describes the known limitations, unsupported and partially supported features, and the potential impact on workloads and API availability when migrating from Open vSwitch (OVS) to Open Virtual Network (OVN). Review these considerations carefully before planning and performing the migration.

Partially supported functionality

Caution

The behavior of partially supported features depends on the specifics of your hardware and software environment. Mirantis strongly recommends conducting additional preparation and testing in a staging environment for such functionality. For further guidance, contact Mirantis support.

  • Environments using SR-IOV ports with floating IP addresses as per upstream #1875852 known issue. This issue impacts scheduling of external ports used in OVN for SR-IOV ports and related router ports, which may lead to loss of connectivity to SR-IOV ports through the floating IP.

  • Networks that require North/South traffic fragmentation as per upstream #2032817 known issue.

  • Routed VLAN/Flat networks as per upstream #1995078 known issue.

Unsupported functionality

  • DPDK acceleration

  • VLAN transparency

  • Migration from OVS with VXLAN to OVN with VXLAN. VXLAN encapsulation is not recommended for OVN and has several limitations compared to OVN with Geneve. The current migration implementation forcefully converts all existing VXLAN networks to Geneve.

  • BGP VPN aaS

  • East-West traffic encryption (IPSec)

  • Networks requiring East-West traffic fragmentation as per upstream #2085099 known issue

  • VPNaaS

  • Floating IP Port Forwarding and DVR as per upstream #2028846 known issue

Impact on workloads availability

Restarting the Networking service (OpenStack Neutron) components during migration may result in temporary workload downtime. The duration of downtime depends on the size and density of the environment.

Impact on cloud API availability

During migration, the Networking service (OpenStack Neutron) API may be unavailable for several hours. While the API is down, new instance creation and most of the Compute and Networking API requests will fail. Plan the maintenance window carefully to minimize API activity in the environment during this period.