# Driver definition [driver.nova-lxd] title=Nova-LXD # Functions: [operation.attach-volume] title=Attach block volume to instance status=optional notes=The attach volume operation provides a means to hotplug additional block storage to a running instance. This allows storage capabilities to be expanded without interruption of service. In a cloud model it would be more typical to just spin up a new instance with large storage, so the ability to hotplug extra storage is for those cases where the instance is considered to be more of a pet than cattle. Therefore this operation is not considered to be mandatory to support. cli=nova volume-attach driver.nova-lxd=complete [operation.attach-tagged-volume] title=Attach tagged block device to instance status=optional notes=Attach a block device with a tag to an existing server instance. See "Device tags" for more information. cli=nova volume-attach [--tag ] driver.nova-lxd=unknown [operation.detach-volume] title=Detach block volume from instance status=optional notes=See notes for attach volume operation. cli=nova volume-detach driver.nova-lxd=missing [operation.extend-volume] title=Extend block volume attached to instance status=optional notes=The extend volume operation provides a means to extend the size of an attached volume. This allows volume size to be expanded without interruption of service. In a cloud model it would be more typical to just spin up a new instance with large storage, so the ability to extend the size of an attached volume is for those cases where the instance is considered to be more of a pet than cattle. Therefore this operation is not considered to be mandatory to support. cli=cinder extend driver.nova-lxd=unknown [operation.attach-interface] title=Attach virtual network interface to instance status=optional notes=The attach interface operation provides a means to hotplug additional interfaces to a running instance. Hotplug support varies between guest OSes and some guests require a reboot for new interfaces to be detected. This operation allows interface capabilities to be expanded without interruption of service. In a cloud model it would be more typical to just spin up a new instance with more interfaces. cli=nova interface-attach driver.nova-lxd=complete [operation.attach-tagged-interface] title=Attach tagged virtual network interface to instance status=optional notes=Attach a virtual network interface with a tag to an existing server instance. See "Device tags" for more information. cli=nova interface-attach [--tag ] driver.nova-lxd=unknown [operation.detach-interface] title=Detach virtual network interface from instance status=optional notes=See notes for attach-interface operation. cli=nova interface-detach driver.nova-lxd=complete [operation.maintenance-mode] title=Set the host in a maintenance mode status=optional notes=This operation allows a host to be placed into maintenance mode, automatically triggering migration of any running instances to an alternative host and preventing new instances from being launched. This is not considered to be a mandatory operation to support. The driver methods to implement are "host_maintenance_mode" and "set_host_enabled". cli=nova host-update driver.nova-lxd=unknown [operation.evacuate] title=Evacuate instances from a host status=optional notes=A possible failure scenario in a cloud environment is the outage of one of the compute nodes. In such a case the instances of the down host can be evacuated to another host. It is assumed that the old host is unlikely ever to be powered back on, otherwise the evacuation attempt will be rejected. When the instances get moved to the new host, their volumes get re-attached and the locally stored data is dropped. That happens in the same way as a rebuild. This is not considered to be a mandatory operation to support. cli=nova evacuate ;nova host-evacuate driver.nova-lxd=complete [operation.rebuild] title=Rebuild instance status=optional notes=A possible use case is additional attributes need to be set to the instance, nova will purge all existing data from the system and remakes the VM with given information such as 'metadata' and 'personalities'. Though this is not considered to be a mandatory operation to support. cli=nova rebuild driver.nova-lxd=complete [operation.get-guest-info] title=Guest instance status status=mandatory notes=Provides realtime information about the power state of the guest instance. Since the power state is used by the compute manager for tracking changes in guests, this operation is considered mandatory to support. cli= driver.nova-lxd=unknown [operation.get-host-uptime] title=Guest host uptime status=optional notes=Returns the result of host uptime since power on, it's used to report hypervisor status. cli= driver.nova-lxd=unknown [operation.get-host-ip] title=Guest host ip status=optional notes=Returns the ip of this host, it's used when doing resize and migration. cli= driver.nova-lxd=unknown [operation.live-migrate] title=Live migrate instance across hosts status=optional notes=Live migration provides a way to move an instance off one compute host, to another compute host. Administrators may use this to evacuate instances from a host that needs to undergo maintenance tasks, though of course this may not help if the host is already suffering a failure. In general instances are considered cattle rather than pets, so it is expected that an instance is liable to be killed if host maintenance is required. It is technically challenging for some hypervisors to provide support for the live migration operation, particularly those built on the container based virtualization. Therefore this operation is not considered mandatory to support. cli=nova live-migration ;nova host-evacuate-live driver.nova-lxd=complete [operation.force-live-migration-to-complete] title=Force live migration to complete status=optional notes=Live migration provides a way to move a running instance to another compute host. But it can sometimes fail to complete if an instance has a high rate of memory or disk page access. This operation provides the user with an option to assist the progress of the live migration. The mechanism used to complete the live migration depends on the underlying virtualization subsystem capabilities. If libvirt/qemu is used and the post-copy feature is available and enabled then the force complete operation will cause a switch to post-copy mode. Otherwise the instance will be suspended until the migration is completed or aborted. cli=nova live-migration-force-complete driver.nova-lxd=unknown [operation.launch] title=Launch instance status=mandatory notes=Importing pre-existing running virtual machines on a host is considered out of scope of the cloud paradigm. Therefore this operation is mandatory to support in drivers. cli= driver.nova-lxd=unknown [operation.pause] title=Stop instance CPUs (pause) status=optional notes=Stopping an instances CPUs can be thought of as roughly equivalent to suspend-to-RAM. The instance is still present in memory, but execution has stopped. The problem, however, is that there is no mechanism to inform the guest OS that this takes place, so upon unpausing, its clocks will no longer report correct time. For this reason hypervisor vendors generally discourage use of this feature and some do not even implement it. Therefore this operation is considered optional to support in drivers. cli=nova pause driver.nova-lxd=complete [operation.reboot] title=Reboot instance status=optional notes=It is reasonable for a guest OS administrator to trigger a graceful reboot from inside the instance. A host initiated graceful reboot requires guest co-operation and a non-graceful reboot can be achieved by a combination of stop+start. Therefore this operation is considered optional. cli=nova reboot driver.nova-lxd=complete [operation.rescue] title=Rescue instance status=optional notes=The rescue operation starts an instance in a special configuration whereby it is booted from an special root disk image. The goal is to allow an administrator to recover the state of a broken virtual machine. In general the cloud model considers instances to be cattle, so if an instance breaks the general expectation is that it be thrown away and a new instance created. Therefore this operation is considered optional to support in drivers. cli=nova rescue driver.nova-lxd=complete [operation.resize] title=Resize instance status=optional notes=The resize operation allows the user to change a running instance to match the size of a different flavor from the one it was initially launched with. There are many different flavor attributes that potentially need to be updated. In general it is technically challenging for a hypervisor to support the alteration of all relevant config settings for a running instance. Therefore this operation is considered optional to support in drivers. cli=nova resize driver.nova-lxd=missing [operation.resume] title=Restore instance status=optional notes=See notes for the suspend operation cli=nova resume driver.nova-lxd=complete [operation.set-admin-password] title=Set instance admin password status=optional notes=Provides a mechanism to (re)set the password of the administrator account inside the instance operating system. This requires that the hypervisor has a way to communicate with the running guest operating system. Given the wide range of operating systems in existence it is unreasonable to expect this to be practical in the general case. The configdrive and metadata service both provide a mechanism for setting the administrator password at initial boot time. In the case where this operation were not available, the administrator would simply have to login to the guest and change the password in the normal manner, so this is just a convenient optimization. Therefore this operation is not considered mandatory for drivers to support. cli=nova set-password driver.nova-lxd=unknown [operation.snapshot] title=Save snapshot of instance disk status=optional notes=The snapshot operation allows the current state of the instance root disk to be saved and uploaded back into the glance image repository. The instance can later be booted again using this saved image. This is in effect making the ephemeral instance root disk into a semi-persistent storage, in so much as it is preserved even though the guest is no longer running. In general though, the expectation is that the root disks are ephemeral so the ability to take a snapshot cannot be assumed. Therefore this operation is not considered mandatory to support. cli=nova image-create driver.nova-lxd=complete [operation.suspend] title=Suspend instance status=optional notes=Suspending an instance can be thought of as roughly equivalent to suspend-to-disk. The instance no longer consumes any RAM or CPUs, with its live running state having been preserved in a file on disk. It can later be restored, at which point it should continue execution where it left off. As with stopping instance CPUs, it suffers from the fact that the guest OS will typically be left with a clock that is no longer telling correct time. For container based virtualization solutions, this operation is particularly technically challenging to implement and is an area of active research. This operation tends to make more sense when thinking of instances as pets, rather than cattle, since with cattle it would be simpler to just terminate the instance instead of suspending. Therefore this operation is considered optional to support. cli=nova suspend driver.nova-lxd=complete [operation.swap-volume] title=Swap block volumes status=optional notes=The swap volume operation is a mechanism for changing a running instance so that its attached volume(s) are backed by different storage in the host. An alternative to this would be to simply terminate the existing instance and spawn a new instance with the new storage. In other words this operation is primarily targeted towards the pet use case rather than cattle, however, it is required for volume migration to work in the volume service. This is considered optional to support. cli=nova volume-update driver.nova-lxd=missing [operation.terminate] title=Shutdown instance status=mandatory notes=The ability to terminate a virtual machine is required in order for a cloud user to stop utilizing resources and thus avoid indefinitely ongoing billing. Therefore this operation is mandatory to support in drivers. cli=nova delete driver.nova-lxd=complete [operation.trigger-crash-dump] title=Trigger crash dump status=optional notes=The trigger crash dump operation is a mechanism for triggering a crash dump in an instance. The feature is typically implemented by injecting an NMI (Non-maskable Interrupt) into the instance. It provides a means to dump the production memory image as a dump file which is useful for users. Therefore this operation is considered optional to support. cli=nova trigger-crash-dump driver.nova-lxd=unknown [operation.unpause] title=Resume instance CPUs (unpause) status=optional notes=See notes for the "Stop instance CPUs" operation cli=nova unpause driver.nova-lxd=unknown [operation.guest.disk.autoconfig] title=[Guest]Auto configure disk status=optional notes=Partition and resize FS to match the size specified by flavors.root_gb, As this is hypervisor specific feature. Therefore this operation is considered optional to support. cli= driver.nova-lxd=complete [operation.guest.disk.rate-limit] title=[Guest]Instance disk I/O limits status=optional notes=The ability to set rate limits on virtual disks allows for greater performance isolation between instances running on the same host storage. It is valid to delegate scheduling of I/O operations to the hypervisor with its default settings, instead of doing fine grained tuning. Therefore this is not considered to be an mandatory configuration to support. cli=nova limits driver.nova-lxd=unknown [operation.guest.setup.configdrive] title=[Guest]Config drive support status=choice(guest.setup) notes=The config drive provides an information channel into the guest operating system, to enable configuration of the administrator password, file injection, registration of SSH keys, etc. Since cloud images typically ship with all login methods locked, a mechanism to set the administrator password or keys is required to get login access. Alternatives include the metadata service and disk injection. At least one of the guest setup mechanisms is required to be supported by drivers, in order to enable login access. cli= driver.nova-lxd=complete [operation.guest.setup.inject.file] title=[Guest]Inject files into disk image status=optional notes=This allows for the end user to provide data for multiple files to be injected into the root filesystem before an instance is booted. This requires that the compute node understand the format of the filesystem and any partitioning scheme it might use on the block device. This is a non-trivial problem considering the vast number of filesystems in existence. The problem of injecting files to a guest OS is better solved by obtaining via the metadata service or config drive. Therefore this operation is considered optional to support. cli= driver.nova-lxd=unknown [operation.guest.setup.inject.networking] title=[Guest]Inject guest networking config status=optional notes=This allows for static networking configuration (IP address, netmask, gateway and routes) to be injected directly into the root filesystem before an instance is booted. This requires that the compute node understand how networking is configured in the guest OS which is a non-trivial problem considering the vast number of operating system types. The problem of configuring networking is better solved by DHCP or by obtaining static config via config drive. Therefore this operation is considered optional to support. cli= driver.nova-lxd=unknown [operation.console.rdp] title=[Console]Remote desktop over RDP status=choice(console) notes=This allows the administrator to interact with the graphical console of the guest OS via RDP. This provides a way to see boot up messages and login to the instance when networking configuration has failed, thus preventing a network based login. Some operating systems may prefer to emit messages via the serial console for easier consumption. Therefore support for this operation is not mandatory, however, a driver is required to support at least one of the listed console access operations. cli=nova get-rdp-console driver.nova-lxd=missing [operation.console.serial.log] title=[Console]View serial console logs status=choice(console) notes=This allows the administrator to query the logs of data emitted by the guest OS on its virtualized serial port. For UNIX guests this typically includes all boot up messages and so is useful for diagnosing problems when an instance fails to successfully boot. Not all guest operating systems will be able to emit boot information on a serial console, others may only support graphical consoles. Therefore support for this operation is not mandatory, however, a driver is required to support at least one of the listed console access operations. cli=nova console-log driver.nova-lxd=complete [operation.console.serial.interactive] title=[Console]Remote interactive serial console status=choice(console) notes=This allows the administrator to interact with the serial console of the guest OS. This provides a way to see boot up messages and login to the instance when networking configuration has failed, thus preventing a network based login. Not all guest operating systems will be able to emit boot information on a serial console, others may only support graphical consoles. Therefore support for this operation is not mandatory, however, a driver is required to support at least one of the listed console access operations. This feature was introduced in the Juno release with blueprint https://blueprints.launchpad.net/nova/+spec/serial-ports cli=nova get-serial-console driver.nova-lxd=unknown [operation.console.spice] title=[Console]Remote desktop over SPICE status=choice(console) notes=This allows the administrator to interact with the graphical console of the guest OS via SPICE. This provides a way to see boot up messages and login to the instance when networking configuration has failed, thus preventing a network based login. Some operating systems may prefer to emit messages via the serial console for easier consumption. Therefore support for this operation is not mandatory, however, a driver is required to support at least one of the listed console access operations. cli=nova get-spice-console driver.nova-lxd=missing [operation.console.vnc] title=[Console]Remote desktop over VNC status=choice(console) notes=This allows the administrator to interact with the graphical console of the guest OS via VNC. This provides a way to see boot up messages and login to the instance when networking configuration has failed, thus preventing a network based login. Some operating systems may prefer to emit messages via the serial console for easier consumption. Therefore support for this operation is not mandatory, however, a driver is required to support at least one of the listed console access operations. cli=nova get-vnc-console driver.nova-lxd=missing [operation.storage.block] title=[Storage]Block storage support status=optional notes=Block storage provides instances with direct attached virtual disks that can be used for persistent storage of data. As an alternative to direct attached disks, an instance may choose to use network based persistent storage. OpenStack provides object storage via the Swift service, or a traditional filesystem such as NFS may be used. Some types of instances may not require persistent storage at all, being simple transaction processing systems reading requests & sending results to and from the network. Therefore support for this configuration is not considered mandatory for drivers to support. cli= driver.nova-lxd=partial driver-notes.nova-lxd=Booting instances from block storages is not supported. [operation.storage.block.backend.fibrechannel] title=[Storage]Block storage over fibre channel status=optional notes=To maximise performance of the block storage, it may be desirable to directly access fibre channel LUNs from the underlying storage technology on the compute hosts. Since this is just a performance optimization of the I/O path it is not considered mandatory to support. cli= driver.nova-lxd=unknown [operation.storage.block.backend.iscsi] title=[Storage]Block storage over iSCSI status=condition(storage.block==complete) notes=If the driver wishes to support block storage, it is common to provide an iSCSI based backend to access the storage from cinder. This isolates the compute layer for knowledge of the specific storage technology used by Cinder, albeit at a potential performance cost due to the longer I/O path involved. If the driver chooses to support block storage, then this is considered mandatory to support, otherwise it is considered optional. cli= driver.nova-lxd=complete [operation.storage.block.backend.iscsi.auth.chap] title=[Storage]CHAP authentication for iSCSI status=optional notes=If accessing the cinder iSCSI service over an untrusted LAN it is desirable to be able to enable authentication for the iSCSI protocol. CHAP is the commonly used authentication protocol for iSCSI. This is not considered mandatory to support. (?) cli= driver.nova-lxd=unknown [operation.storage.block.ceph] title=[Storage]Block storage over RBD(Ceph) status=condition(storage.block==complete) notes=Ceph is an open source software storage platform based upon RADOS. Instances can access to the ceph storage cluster by ceph's RBD(RADOS Block Device). cli= driver.nova-lxd=complete [operation.storage.image] title=[Storage]Image storage support status=mandatory notes=This refers to the ability to boot an instance from an image stored in the glance image repository. Without this feature it would not be possible to bootstrap from a clean environment, since there would be no way to get block volumes populated and reliance on external PXE servers is out of scope. Therefore this is considered a mandatory storage feature to support. cli=nova boot --image driver.nova-lxd=complete [operation.networking.firewallrules] title=[Networking]Network firewall rules status=optional notes=Unclear how this is different from security groups cli= driver.nova-lxd=complete [operation.networking.routing] title=Network routing status=optional notes=Unclear what this refers to cli= driver.nova-lxd=complete [operation.networking.securitygroups] title=[Networking]Network security groups status=optional notes=The security groups feature provides a way to define rules to isolate the network traffic of different instances running on a compute host. This would prevent actions such as MAC and IP address spoofing, or the ability to setup rogue DHCP servers. In a private cloud environment this may be considered to be a superfluous requirement. Therefore this is considered to be an optional configuration to support. cli= driver.nova-lxd=complete [operation.networking.topology.flat] title=[Networking]Flat networking status=choice(networking.topology) notes=Provide network connectivity to guests using a flat topology across all compute nodes. At least one of the networking configurations is mandatory to support in the drivers. cli= driver.nova-lxd=complete [operation.networking.topology.vlan] title=[Networking]VLAN networking status=choice(networking.topology) notes=Provide network connectivity to guests using VLANs to define the topology. At least one of the networking configurations is mandatory to support in the drivers. cli= driver.nova-lxd=complete [operation.networking.topology.vxlan] title=[Networking]VXLAN networking status=choice(networking.topology) notes=Provide network connectivity to guests using VXLANs to define the topology. At least one of the networking configurations is mandatory to support in the drivers. cli= driver.nova-lxd=complete [operation.uefi-boot] title=uefi boot status=optional notes=This allows users to boot a guest with uefi firmware. cli= driver.nova-lxd=unknown [operation.device-tags] title=Device tags status=optional notes=This allows users to set tags on virtual devices when creating a server instance. Device tags are used to identify virtual device metadata, as exposed in the metadata API and on the config drive. For example, a network interface tagged with "nic1" will appear in the metadata along with its bus (ex: PCI), bus address (ex: 0000:00:02.0), MAC address, and tag (nic1). If multiple networks are defined, the order in which they appear in the guest operating system will not necessarily reflect the order in which they are given in the server boot request. Guests should therefore not depend on device order to deduce any information about their network devices. Instead, device role tags should be used. Device tags can be applied to virtual network interfaces and block devices. cli=nova boot driver.nova-lxd=unknown [operation.quiesce] title=quiesce status=optional notes=Quiesce the specified instance to prepare for snapshots. For libvirt, guest filesystems will be frozen through qemu agent. cli= driver.nova-lxd=unknown [operation.unquiesce] title=unquiesce status=optional notes=See notes for the quiesce operation cli= driver.nova-lxd=unknown [operation.multiattach-volume] title=Attach block volume to multiple instances status=optional notes=The multiattach volume operation is an extension to the attach volume operation. It allows to attach a single volume to multiple instances. This operation is not considered to be mandatory to support. Note that for the libvirt driver, this is only supported if qemu<2.10 or libvirt>=3.10. cli=nova volume-attach driver.nova-lxd=unknown [operation.encrypted-volume] title=Attach encrypted block volume to server status=optional notes=This is the same as the attach volume operation except with an encrypted block device. Encrypted volumes are controlled via admin-configured volume types in the block storage service. Since attach volume is optional this feature is also optional for compute drivers to support. cli=nova volume-attach driver.nova-lxd=unknown [operation.trusted-certs] title=Validate image with trusted certificates status=optional notes=Since trusted image certification validation is configurable by the cloud deployer it is considered optional. However, it is a virt-agnostic feature so there is no good reason that all virt drivers cannot support the feature since it is mostly just plumbing user requests through the virt driver when downloading images. cli=nova boot --trusted-image-certificate-id ... driver.nova-lxd=unknown [operation.file-backed-memory] title=File backed memory status=optional notes=The file backed memory feature in Openstack allows a Nova node to serve guest memory from a file backing store. This mechanism uses the libvirt file memory source, causing guest instance memory to be allocated as files within the libvirt memory backing directory. This is only supported if qemu>2.6 and libivrt>4.0.0 cli= driver.nova-lxd=unknown [operation.report-cpu-traits] title=Report CPU traits status=optional notes=The report CPU traits feature in OpenStack allows a Nova node to report its CPU traits according to CPU mode configuration. This gives users the ability to boot instances based on desired CPU traits. cli= driver.nova-lxd=unknown