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HSQUEEZE(1) Ganeti | Version @GANETI_VERSION@

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NAME

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hsqueeze \- Dynamic power management

SYNOPSIS

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**hsqueeze** {backend options...} [algorithm options...] [reporting options...]

**hsqueeze** \--version

Backend options:

{ **-L[** *path* **]** | **-t** *data-file* }

Algorithm options:

**[ \--minimal-resources=*factor* ]**

**[ \--target-resources=*factor* ]**

Reporting options:

**[ -S *file* ]**

**[ -C[*file*] ]**

DESCRIPTION

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hsqueeze does dynamic power management, by powering up or shutting down nodes,

depending on the current load of the cluster. Currently, only suggesting nodes

is implemented.

ALGORITHM

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hsqueeze considers all online non-master nodes with only externally mirrored

instances as candidates for being taken offline. These nodes are iteratively,

starting from the node with the least number of instances, added to the set

of nodes to be put offline, if possible. A set of nodes is considered as suitable

for being taken offline, if, after marking these nodes as offline, balancing the

cluster by the algorithm used by **hbal**\(1) yields a situation where all instances

are located on online nodes, and each node has at least the target resources free

for new instances.

All offline nodes with a tag starting with ``htools:standby`` are

considered candidates for being taken online. Those nodes are taken online

till balancing the cluster by the algorithm used by **hbal**\(1) yields a

situation where each node has at least the minimal resources free for new

instances.

OPTIONS

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-L [*path*]

  Backend specification: collect data directly from the master daemon,

  which is to be contacted via LUXI (an internal Ganeti protocol). The

  option is described in the man page **htools**\(1).

-S *filename*, \--save-cluster=*filename*

  If given, the state of the cluster before the squeezing is saved to

  the given file plus the extension "original"

  (i.e. *filename*.original), and the state at the end of the

  squeezing operation is saved to the given file plus the extension "squeezed"

  (i.e. *filename*.squeezed).

-C[*filename*], \--print-commands[=*filename*]

  If given, a shell script containing the commands to squeeze or unsqueeze

  the cluster are saved in a file with the given name; if no name is provided,

  they are printed to stdout.

-t *datafile*, \--text-data=*datafile*

  Backend specification: the name of the file holding node and instance

  information (if not collecting LUXI). This or one of the

  other backends must be selected. The option is described in the man

  page **htools**\(1).

\--minimal-resources=*factor*

  Specify the amount of resources to be free on each node for hsqueeze not to

  consider onlining additional nodes. The value is reported a multiple of the

  standard instance specification, as taken from the instance policy.

\--target-resources=*factor*

  Specify the amount of resources to remain free on any node after squeezing.

  The value is reported a multiple of the standard instance specification, as

  taken from the instance policy.