--- deprecations: - | The ``[libvirt]live_migration_tunnelled`` option is deprecated as of Wallaby (23.0.0) release. The "tunnelled live migration" has two inherent limitations: (a) it cannot handle live migration of disks in a non-shared storage setup, and (b) it has a huge performance overhead and latency, because it burns more CPU and memory during live migration. Both these problems are addressed by the QEMU-native support in Nova -- this is the recommended approach for securing all live migration streams (guest RAM, device state, and disks). Assuming TLS environment is setup, this can be enabled by setting the config attribute ``[libvirt]live_migration_with_native_tls``.