SYNOPSIS
--------
-**hail** [ **-t** *file* | **--simulate** *spec* ] [options...] *input-file*
+**hail** [ **-t** *file* | **\--simulate** *spec* ] [options...] *input-file*
-**hail** --version
+**hail** \--version
DESCRIPTION
-----------
hail is a Ganeti IAllocator plugin that implements the instance
-placement and movement using the same algorithm as **hbal**(1).
+placement and movement using the same algorithm as **hbal**\(1).
The program takes input via a JSON-file containing current cluster
state and the request details, and output (on stdout) a JSON-formatted
response. In case of critical failures, the error message is printed
on stderr and the exit code is changed to show failure.
+If the input file name is ``-`` (a single minus sign), then the request
+data will be read from *stdin*.
+
ALGORITHM
~~~~~~~~~
The options that can be passed to the program are as follows:
--p, --print-nodes
+-p, \--print-nodes
Prints the before and after node status, in a format designed to allow
the user to understand the node's most important parameters. See the
- man page **htools**(1) for more details about this option.
+ man page **htools**\(1) for more details about this option.
--t *datafile*, --text-data=*datafile*
- The name of the file holding cluster information, to override the
- data in the JSON request itself. This is mostly used for debugging.
+-t *datafile*, \--text-data=*datafile*
+ The name of the file holding cluster information, to override the data
+ in the JSON request itself. This is mostly used for debugging. The
+ format of the file is described in the man page **htools**\(1).
---simulate *description*
- Similar to the **-t** option, this allows overriding the cluster
- data with a simulated cluster. For details about the description,
- see the man page **hspace**(1).
+\--simulate *description*
+ Backend specification: similar to the **-t** option, this allows
+ overriding the cluster data with a simulated cluster. For details
+ about the description, see the man page **htools**\(1).
--S *filename*, --save-cluster=*filename*
+-S *filename*, \--save-cluster=*filename*
If given, the state of the cluster before and the iallocator run is
saved to a file named *filename.pre-ialloc*, respectively
*filename.post-ialloc*. This allows re-feeding the cluster state to
- any of the htools utilities.
+ any of the htools utilities via the ``-t`` option.
-v
This option increases verbosity and can be used for debugging in order
The exist status of the command will be zero, unless for some reason
the algorithm fatally failed (e.g. wrong node or instance data).
+BUGS
+----
+
+Networks (as configured by **gnt-network**\(8)) are not taken into
+account in Ganeti 2.7. The only way to guarantee that they work
+correctly is having your networks connected to all nodegroups. This will
+be fixed in a future version.
+
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