[[PageOutline]] 

= QCG-Notification Installation in PL-Grid=
This document describes basic procedures needed to install QCG-Notification on the PL-Grid resources as a part of the !QosCosGrid middleware. Within !QosCosGrid the QCG-Notification service is used for brokering notification messages about the job state changes. All instances of the QCG-Computing services acts as the information ''Producers'' while the QCG-Broker as the ''Consumer''. In most cases it is enough that only one instance of the QCG-Notification is deployed per Administrative Domain (i.e.: not necessary one per Cluster). You can install the QCG-Notification service on the same machine where the [[http://www.qoscosgrid.org/trac/qcg-computing|QCG-Computing service]] is installed. 

= Installation =
Similarly to the [[http://www.qoscosgrid.org/trac/qcg-computing/installation_in_PL-Grid|QCG-Computing service]] service, QCG-Notification may be installed from the provided RPMs. Assuming that the QCG-Computing service has been installed and initially configured (thus the basic dependencies are satisfied), the procedure is as follows:

* ensure that the qcg-ntf user is present in a system, otherwise create it:
{{{
#!div style="font-size: 90%"
{{{#!sh
useradd -d /opt/plgrid/var/log/qcg-ntf/ qcg-ntf
}}}
}}}

* install PL-Grid (official) and QCG (testing) repositories, if you have not done this yet.:
{{{
#!div style="font-size: 90%"
{{{#!sh
#QosCosGrid testing repository
cat > /etc/yum.repos.d/qcg.repo << EOF
[qcg]
name=QosCosGrid YUM repository
baseurl=http://fury.man.poznan.pl/qcg-packages/sl/x86_64/
enabled=1
gpgcheck=0
EOF
  
#Official PL-Grid repository
rpm -Uvh http://software.plgrid.pl/packages/repos/plgrid-repos-2010-2.noarch.rpm
}}}
}}}

* install QCG-Notification using YUM Package Manager:
{{{
#!div style="font-size: 90%"
{{{#!sh
yum install qcg-ntf
}}}
}}}

* setup QCG-Notification database using provided script:
{{{
#!div style="font-size: 90%"
{{{#!sh
/opt/plgrid/qcg/share/qcg-ntf/tools/qcg-ntf-install.sh
Welcome to qcg-ntf installation script!

This script will guide you through process of configuring proper environment
for running the QCG-Notification service. You have to answer few questions regarding
parameters of your database. If you are not sure just press Enter and use the
default values.
  
Use local PostgreSQL server? (y/n) [y]: y
Database [qcg-ntf]: 
User [qcg-ntf]: 
Password [qcg-ntf]: MojeTajneHaslo
Create database? (y/n) [y]: y
Create user? (y/n) [y]: y
  
Checking for system user qcg_ntf...OK
Checking whether PostgreSQL server is installed...OK
Checking whether PostgreSQL server is running...OK
  
Performing installation
* Creating user qcg-ntf...OK
* Creating database qcg-ntf...OK
* Creating database schema...OK
* Checking for ODBC data source qcg-ntf...
* Installing ODBC data source...OK
    
Remember to add appropriate entry to /var/lib/pgsql/data/pg_hba.conf (as the first rule!) to allow user qcg-ntf to
access database qcg-ntf. For instance:
  
host    qcg-ntf       qcg-ntf       127.0.0.1/32    md5
  
and reload Postgres server.
}}}
}}}
 

* Add a new rule to the pg_hba.conf as requested:
{{{
#!div style="font-size: 90%"
{{{#!sh
vim /var/lib/pgsql/data/pg_hba.conf 
/etc/init.d/postgresql reload
}}}
}}}

= Configuration =

== Service configuration ==
The service should be ready to use "out-of-the-box", however basic configuration may be needed to setup ''Host'' and ''Port'' on which QCG-Notification should listen as well as parameters of database connection: ''DSN'', ''User'' and ''Password''. It can be done by editing the main QCG-Notification configuration file located in: `/opt/plgrid/qcg/etc/qcg-ntfd.xml`. A part of the configuration file with marked key parameters is presented below:
{{{
#!div style="font-size: 90%"
{{{#!xml
<sm:QCGCore 
   <Configuration>
   ....
              <sm:Module xsi:type="sm:ecm_gsoap.service">
                  <sm:Host>127.0.0.1</sm:Host>
                  <sm:Port>19001</sm:Port>
                  <sm:UseWsa>true</sm:UseWsa>
              </sm:Module>
   ....
              <smn:Database>
                  <smn:DatabaseEnabled>true</smn:DatabaseEnabled>
                  <smn:DSN>qcg-ntf</smn:DSN>
                  <smn:User>qcg-ntf</smn:User>
                  <smn:Password>qcg-ntf</smn:Password>
                  <smn:CleanAtStart>false</smn:CleanAtStart>
              </smn:Database>
   ....
   </Configuration>
</sm:QCGCore>
}}}
}}}

For more information about configuration of the service please take a look at the QCG-Notification guide installed in the `/opt/plgrid/qcg/share/qcg-ntf/doc/` directory. 

After finishing the QCG-Notification configuration you must edit the QCG-Computing service configuration file and update the content of the `<ServiceURL>` elements (in `<Module xsi:type="smc:notification_wsa">` section). For e.g. if in the  `/opt/plgrid/qcg/etc/qcg-ntfd.xml` one can find  `<Host>example.com<Host>` and `<Port>19001<Port>` the `<ServiceURL>` must be set to `http://example.com:19001/`. 

'''Note:''' You must restart the QCG-Computing service after updating the `qcg-compd.xml` configuration file.

= Running the service =
The QCG-Notification initialization script is automatically added to `init.d` directory and may be run as a standard system service:
{{{
#!div style="font-size: 90%"
{{{#!sh 
/etc/init.d/qcg-ntfd start
}}}
}}}

The service logs can be found in:
{{{
#!div style="font-size: 90%"
{{{#!sh
/opt/plgrid/var/log/qcg-ntf/qcg-ntfd.log
}}}
}}}

It could be then stopped with the following command:
{{{
#!div style="font-size: 90%"
{{{#!sh
/etc/init.d/qcg-ntfd stop
}}}
}}}
'''Note:''' `qcg-ntfd` will be started with the `qcg_ntf` user permissions.

= Verifying the installation =
After starting the QCG-Notification service and updating the QCG-Computing configuration try to submit a simple job and check the QCG-Computing log file to see if there are now any error messages on sending notifications, e.g.:
{{{
#!div style="font-size: 90%"
{{{#!sh
tail -f /opt/plgrid/var/log/qcg-comp/qcg-compd.log
INF Sep 17 16:15:01 24201 0x44b22940 [notification_ws] Sending notify message (topic = ActivityState/TerminalState/Finished, activity_id = 0544b24a-e960-400e-4910-f1a893632610, status = Finished)
}}}
}}}

= Configuring firewall=
Please have a look at [[http://www.qoscosgrid.org/trac/qcg-computing/installation_in_PL-Grid#Configuringfirewall| this section]].