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manual:3gbplugin-glite

gLite plugin for the 3G Bridge

This is an installation manual for deploying the gLite pluing under 3G Bridge.

1. Prerequisites

  • at least one CPU
  • at least 512M RAM recommended
  • at least 1G of free HDD space recommended
  • Scientific Linux 4 with preconfigured gLite 3.1 or Scientific Linux 5 with preconfigured gLite 3.2 (preferred)
  • MySQL server installed on the machine
  • gLite VO membership

2. Set up the EDGeS/EDGI YUM repository

Scientific Linux 4:

# cat /etc/yum.repos.d/edges.repo
[edges]
name=EDGeS Grid Deployment
baseurl=http://intraweb.edges-grid.eu/public/grid_deployment/repo
enabled=1

Scientific Linux 5:

# cat /etc/yum.repos.d/edgi.repo
[edgi]
name=EDGI Grid Deployment
baseurl=http://www.edgi-grid.eu/downloads/repo/sl5
enabled=1
protect=1

3. Install the necessary packages

  • Scientific Linux 4:
    • 3g-bridge
  • Scientific Linux 5:
    • 3g-bridge
    • 3g-bridge-plugin-egee

4a. Install core 3G Bridge

This part of the installation can be skipped if the 3G Bridge software is already installed and operational on your machine.

  • It is recommended to create a new user account that will run the bridge
$ adduser 3g-bridge

(Installing from an rpm package does this at installation so you can skip this step if using a packaged version.)

  • Create a database for the bridge on the MySQL server
mysql> create database bridge;
mysql> grant all privileges on bridge.* to bridge identified by 'some_password';

(In this example the both the database and the user to access it are called bridge.)

  • Create the necessary tables in the database:
$ mysql -u bridge -p bridge < doc/db/schema.sql

or update an existing database:

$ mysql -u bridge -p bridge < doc/db/schema-update.sql

4b. Configure the gLite plugin for 3G Bridge

  • Configure the bridge:
    • Update [database] access informations in /etc/3g-bridge.conf
    • Create a queue:
mysql> insert into cg_algqueue(grid, alg, batchsize) values('boincgrid', '', 10);

Here, we create a queue for the plugin instance named 'boincgrid' that supports submitting at most 10 jobs in one collection (The collection size determines the maximum number of jobs passed to the WMS in one communication session.

  • Set up an EGEE plugin instance as the target in /etc/3g-bridge.conf. You have to set up the following properties:
    • name of the plugin instance surrounded by “[” and “]” e.g. [boincgrid]
    • the plugin's type: 'handler = EGEE'
    • the VO name to use: 'voname = gilda'
    • the WMProxy endpoint for the VO
    • MyProxy setings for retrieving proxies (see MyProxy configuration below)
    • set the GridFTP URL prefix for storing input and output files of jobs through the isb_url attribute
  • Start the bridge:
$ 3g-bridge -c 3g-bridge.conf

The rpm package also contains an init script that can be used instead:

$ service 3g-bridge start

the latter variation expects the config file to be /etc/3g-bridge.conf

  • In order to add a new BOINC → EGEE path to the already running bridge, the following steps must be executed:
    • Step from “Create a queue” to “Start the bridge” from above. Note: if you plan to use an already existing EGEE plugin instance for executing jobs from the new BOINC server, step “Set up an EGEE plugin instance” can be skipped.
    • Stop the bridge, the following command stops a bridge running as a daemon
$ 3g-bridge -c 3g-bridge.conf –k
  • Start the bridge (as explained above)

5.Remarks

It is recommended to start the different components either as a backgroundprocess or in a screen terminal. The bridge by defaults detaches from the terminal and becomes a daemon. This can be changed with the -f option.If running as a deamon the bridge logs to syslog then after it could read its config file it uses the log-target specified therein.

6.Configuring a MyProxy server to support proxy retrieval

The gLite plugin needs a valid proxy to access gLite resources. These are retrieved from a myproxy server by each plugin instance as specified in the config file by the following parameters:

myproxy_host = myproxy.server.domain
myproxy_port = 7512
myproxy_user = /O=grid/O=Organisation/CN=Grid User
myproxy_authcert = /etc/grid-security/bridge.cert
myproxy_authkey = /etc/grid-security/bridge.key

Most of these are self explanatory, the authcert and authkey are credentials used to authenticate to the MyProxy server to retrieve a proxy belonging to user (this is the user that the job will be submitted as). To allow this the following configuration options are required in myproxy-server.conf on the MyProxy server side:

authorized_retrievers "/O=grid/O=Service/CN=bridge"
trusted_retrievers "/O=grid/O=Service/CN=bridge"
default_trusted_retrievers "/O=grid/O=Service/CN=bridge"

where “/O=grid/O=Service/CN=bridge” is the subject of bridge.cert above. Users whose WUs are to be sent through the bridge should delegate their proxy first with the following command:

$ GT_PROXY_MODE=old myproxy-init -s myproxy.server.domain -d -n

and then keep it up to date as long as they want to use gLite resources through the bridge.

manual/3gbplugin-glite.txt · Last modified: 2013/01/18 09:51 by smith