Revision 11a0e343 doc/glossary.rst

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  ballooning
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    A term describing runtime, dynamic changes to an instance's memory,
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    without having to reboot the instance. Depending on the hypervisor
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    and configuration, the changes need to be initiated manually, or
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    they can be automatically initiated by the hypervisor based on the
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    node and instances memory usage.
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    A term describing dynamic changes to an instance's memory while the instance
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    is running that don't require an instance reboot. Depending on the
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    hypervisor and configuration, changes may be automatically initiated by the
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    hypervisor (based on the memory usage of the node and instance), or may need
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    to be initiated manually.
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  BE parameter
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    BE stands for *backend*. BE parameters are hypervisor-independent
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    instance parameters such as the amount of RAM/virtual CPUs it has
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    been allocated.
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    BE stands for *backend*. BE parameters are hypervisor-independent instance
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    parameters, such as the amount of RAM/virtual CPUs allocated to an instance.
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  DRBD
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    A block device driver that can be used to build RAID1 across the
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    network or even shared storage, while using only locally-attached
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    storage.
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    A block device driver that can be used to build RAID1 across the network or
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    across shared storage, while using only locally-attached storage.
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  HV parameter
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    HV stands for *hypervisor*. HV parameters are the ones that describe
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    the virtualization-specific aspects of the instance; for example,
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    what kernel to use to boot the instance (if any), or what emulation
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    model to use for the emulated hard drives.
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    HV stands for *hypervisor*. HV parameters describe the virtualization-
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    specific aspects of the instance. For example, a HV parameter might describe
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    what kernel (if any) to use to boot the instance or what emulation model to
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    use for the emulated hard drives.
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  HVM
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    Hardware virtualization mode, where the virtual machine is oblivious
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    to the fact that's being virtualized and all the hardware is
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    *Hardware Virtualization Mode*. In this mode, the virtual machine is
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    oblivious to the fact that it is virtualized and all its hardware is
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    emulated.
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  LogicalUnit
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    The code associated with an :term:`OpCode`, e.g. the code that
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    The code associated with an :term:`OpCode`; for example, the code that
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    implements the startup of an instance.
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  LUXI
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     Local UniX Interface. The IPC method over :manpage:`unix(7)`
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     sockets used between the CLI tools/RAPI daemon and the master
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     daemon.
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     Local UniX Interface. The IPC method over :manpage:`unix(7)` sockets used
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     between the CLI tools/RAPI daemon and the master daemon.
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  OOB
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    *Out of Band*. This term describes methods of accessing a machine
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    (or parts of a machine) not via the usual network connection. For
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    example, accessing a remote server via a physical serial console or
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    via a virtual one IPMI counts as out of band access.
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    *Out of Band*. This term describes methods of accessing a machine (or parts
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    of a machine) by means other than the usual network connection.  Examples
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    include accessing a remote server via a physical serial console or via a
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    virtual console. IPMI is also considered OOB access.
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  OpCode
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    A data structure encapsulating a basic cluster operation; for
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    example, start instance, add instance, etc.
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    A data structure encapsulating a basic cluster operation; for example: start
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    instance, add instance, etc.
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  PVM
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    (Xen) Para-virtualization mode, where the virtual machine knows it's
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    being virtualized and as such there is no need for hardware
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    emulation or virtualization.
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    (Xen) *Para-virtualization mode*. In this mode, the virtual machine is aware
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    that it is virtualized; therefore, there is no need for hardware emulation
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    or virtualization.
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  SoR
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    *State of Record*. Refers to values/properties that come from an
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    authoritative configuration source. For example, the maximum VCPU
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    over-subscription ratio is a *SoR* value, but the current
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    over-subscription ration (based on how many instances live on the
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    node) is a :term:`SoW` value.
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    authoritative configuration source. For example, the maximum VCPU over-
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    subscription ratio is a SoR value, but the current over-subscription ratio
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    (based upon how many instances live on the node) is a :term:`SoW` value.
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  SoW
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    *State of the World*. Refers to values that describe directly the
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    world, as opposed to values that come from the
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    configuration. Contrast with :term:`SoR`.
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    *State of the World*. Refers to values that directly describe the world, as
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    opposed to values that come from the configuration (which are considered
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    :term:`SoR`).
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  tmem
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    Xen Transcendent Memory
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    (http://en.wikipedia.org/wiki/Transcendent_memory). It is a
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    mechanism used by Xen to provide memory over-subscription.
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    Xen Transcendent Memory (http://en.wikipedia.org/wiki/Transcendent_memory).
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    tmem is a mechanism used by Xen to provide memory over-subscription.
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  watcher
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    :command:`ganeti-watcher` is a tool that should be run regularly
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    from cron and takes care of restarting failed instances, restarting
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    secondary DRBD devices, etc. For more details, see the man page
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    :command:`ganeti-watcher` is a tool that should be run regularly from
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    cron. The tool executes tasks such as restarting failed instances and
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    restarting secondary DRBD devices. For more details, see the man page
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    :manpage:`ganeti-watcher(8)`.
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