= How to add Neptuno facilities to WRF4G =

WRF4G uses [wiki:DRM4G DRM4G] to access to different Distributed Resource Managements (DRM) such as:

* PBS/Torque
* SGE
* FORK
* !LoadLeveler
* '''SLURM'''
 
In order to add new resources, you need to edit [wiki:WRF4Gframework4g_conf#ComputingResources Computing Resources] section in the [wiki:WRF4Gframework4g_conf framework4g.conf] file, which is located under `$HOME/WRF4G/etc` directory. The file has to contain one resource per line with the format:

{{{
   resource_name  = attributes
   ...     ...
   resource_name  = attributes
}}}

where:
* '''resource_name''': It is the name of the CR.
* '''attributes''': They are the static attributes of the CR. The syntax is:
 * `<scheme>://<username>@<host:port>?<query>`
  * '''scheme''':  URL schemes available are "ssh" and "local".
    * '''ssh''':   In order to connect to remote resource via SSH
    * '''local''': In order to use a local resource
  * '''username''': user name on the resource
  * '''host''': host name
  * '''port''': host port. By DEFAULT it is 22
  * '''query''': contains additional information of computing resources. The query string syntax is:
    * key1=value1;key2=value2;key3=value3

The keys available are:
* '''LRMS_TYPE'''(mandatory): Type of LRMS system ('''neptuno''')
* '''NODECOUNT'''(mandatory): Maximum number of job slots for a resource.
* '''SSH_KEY_FILE'''(optional): It defines the key file for "ssh" connection. By DEFAULT it is ~/.ssh/id_rsa.
* '''TEMP_DIR'''(optional): Temporary directory on the resource to store data. By DEFAULT it is `$HOME`. TEMP_DIR path must be absolute.
* '''RUN_DIR'''(optional): Temporary directory used to run WRF Model on the resource. By DEFAULT it is `$HOME`. RUN_DIR path must be absolute.

Example of configuration:

{{{
neptuno =  ssh://userid@193.144.213.182?LRMS_TYPE=neptuno;NODECOUNT=1500
}}}

If you want to configure Neptuno facilities using '''ssh''' protocol, you need to set up SSH login without ''password'' (see [wiki:DRM4G#AppendixB Appendix B]) between '''MACC cluster''' and '''Neptuno''', and '''vice-versa'''. 


[[NoteBox(warn, After modifying `ComputingResources` section\, WRF4G takes few seconds in order to update the changes)]] 

In addition, you need to update `WRF4G_BASEPATH`, `WRF4G_DOMAINPATH`, `WRF4G_INPUT` and `WRF4G_APPS` variables, which are defined in [wiki:WRF4Gresources_wrf4g  resources.wrf4g ] file. Due to the fact that these variables may point to other machines. See [wiki:WRF4Gresources_wrf4g#Runningenvironment running environment ] for more information.

Example of configuration:

{{{
WRF4G_BASEPATH="rsync://userid_macc@193.144.213.182/home/users/user_neptuno/output" 
WRF4G_DOMAINPATH="rsync://userid_macc@193.144.184.31/work/gihc/repository/domains"
WRF4G_INPUT="rsync://userid_macc@193.144.184.31/work/gihc/repository/input"
WRF4G_APPS="rsync://userid_macc@193.144.184.31/work/gihc/repository/apps"
}}}

= Neptuno Running Options =

NP
    Number of processors requested in a parallel job. Note that it has to be enough resources to run. For example, if we only configure 1 processor (NODECOUNT=1) of a computer in framework4g.conf, WRF4G can not submit an experiment demanding NP=2. 

    If you are going to use PBS/Torque or SLURM resources, it is also highly recommendable to use PPN variable in order to indicate the number of processors available per node. For example, NP = 4 and REQUIREMENTS = 'PPN = 4' which means 4 processors on one node

REQUIREMENTS
    Requirements asked to the CRs where the experiment is going to run (for more information see advanced configuration). For example, REQUIREMENTS ='HOSTNAME = "mycomputer"'. 

ENVIRONMENT
    Experiment environment variables are configuration options for the jobs (for more information see advanced configuration). For example, ENVIRONMENT = 'WALLTIME = 01:00:00' (one hour of max walltime).