INSTALLING HELIOS
Installing Helios isn't terribly hard itself, but it does require
several prerequisites. This file details the necessary steps for several
operating systems, and the generic steps necessary for other platforms.
The general steps involve:
* Install MySQL
* Install Apache or other web server (to support the job submission CGI)
* Install required Perl modules
* Install Helios
* Configure Helios database and .ini file
In general, you should probably install your MySQL database and Apache
server(s), then install Helios and its prerequisites on one server. Once you
have a one-node collective running, installing and running Helios on other
hosts will be easier.
GENERIC INSTRUCTIONS
The following instructions should work to install Helios on most Unix-style
platforms. If your platform has some of these things prepackaged (MySQL and
Apache, hopefully), you can save yourself some time by using the prepackaged
versions.
1) Install MySQL
You'll need to install MySQL and create a database and a user that all the
Helios hosts can log into. The sql/helios.sql file contains the schema for
the Helios database; you can go ahead and create it now or wait until you're
ready to install Helios.
2) Install Apache
Install Apache on the host(s) you want to send HTTP to submit jobs. This
server(s) will need to have the same database access as the other Helios
hosts, regardless of whether it will be running jobs. It's probably best to
simply use your first host for this, at least until your get the rest of your
Helios collective up and running. Make sure Apache is configured to run CGI
programs.
You could also use another HTTP server with CGI capabilities. There's no
reason it shouldn't work, but Helios hasn't been tested with other web servers,
so YMMV.
If you don't want to submit jobs via HTTP, you don't have to install Apache,
though the Helios::Panoptes admin interface (packaged separately) will still
need it.
3) Install Perl CPAN dependencies
Helios requires the following modules to be installed:
DBI
DBD::mysql
XML::Simple
Sys::Syslog
Config::IniFiles
Error
Data::ObjectDriver
TheSchwartz
Bundle::LWP
Some of these modules have dependencies of their own. Your best bet in most
cases is to try to use the CPAN shell (perl -MCPAN -eshell) to install these
libraries. In most cases the CPAN shell will be able to install the proper
dependencies. One exception is XML::Simple, which requires an underlying XML
parser, either XML::Parser or XML::LibXML; these always seem to cause
installation problems for the author in one way or another. Using a .deb or
.rpm to install the XML parser will probably save you a lot of time and
headache.
4) Install Helios
You can install Helios in the typical CPAN manner:
perl Makefile.PL
make
make test
make install
If the HELIOS_INI environment variable is set (see below), make test will
attempt to use the information in the .ini file to connect to the specified
Helios database and read configuration parameters from it. If HELIOS_INI isn't
set, that test will be skipped.
Once the Helios base libraries are installed, you can optionally install the
job submission CGI in your host's cgi-bin directory to support job submission
via HTTP. If your cgi-bin directory is, say, /usr/local/apache/cgi-bin:
cp cgi-bin/submitJob.pl /usr/local/apache/cgi-bin/
should put submitJob.pl in the right place. Remember to make the file
executable by your web server's user.
5) Initial Helios configuration - helios.ini
Just about everything in Helios depends on a helios.ini file to specify
initial settings and connection information for the Helios database. The
helios.pl daemon service loader/daemon program will look for its .ini file in
the location specified by the HELIOS_INI environment variable, so adding
export HELIOS_INI=/path/to/helios.ini
to either your global user profile or the profile of the user you intend to run
Helios under is probably a good idea.
There is a sample helios.ini file included in the Helios distribution to help
guide your initial install. To specify the Helios database connection, specify
the correct dsn, user, and password values in the [global] section. Helios by
default will place PID files for the daemons it launches in /var/run/helios;
you may want to change this location by specifying the pid_path parameter.
There are other parameters you can specify; check the helios.pl man page for
more information.
6) Initial Helios configuration - Helios database
The sql/helios.sql file contains the schema for the Helios database. You can
set up the Helios schema in your database by feeding the SQL commands to your
mysql command line client:
mysql -D database -u user -p < sql/helios.sql
7) Final checks
At this point, your Helios host should be ready to service jobs. If you want
to do further tests, you can use Helios::TestService. Helios::TestService
runs in your Helios collective like any other service, but it only records the
job arguments passed to it in the Helios log. Once you're satisfied your
Helios host is configured properly, you can move on to installing Helios on the
next host in your collective.
UBUNTU / DEBIAN INSTALL
Most of the Helios requirements can be installed on an Ubuntu system using
apt-get. These steps were used on Ubuntu 8.04 Hardy Heron; older Ubuntu
versions may not have the correct libraries. Debian should have these
libraries and more, so some of the CPAN modules you'll need to install directly
from CPAN with Ubuntu have already been packaged and are ready to go with
Debian.
1) Install MySQL
apt-get install mysql-server
The mysql-server package will also install the Perl DBI and DBD::mysql modules,
if they aren't already installed.
2) Install Apache
apt-get install apache2
3) Install XML::Simple
apt-get install libxml-simple-perl
The libxml-simple-perl package will also install its necessary prerequisites,
including XML::LibXML, XML::SAX, XML::NamespaceSupport.
4) Install miscellaneous modules - Sys::Syslog, Config::IniFiles, Error
apt-get install libsys-syslog-perl
apt-get install libconfig-inifiles-perl
apt-get install liberror-perl
5) Ubuntu's repositories unfortunately don't have debs past this point. Use
the CPAN shell (perl -MCPAN -eshell) to install the following modules or
download and install them manually. (NOTE: Debian does have some or all of
these available, so if you're running Debian you may try running apt-get to
install the following modules.
Data::ObjectDriver
TheSchwartz
Data::ObjectDriver in particular has several dependencies that are not part of
the Perl core. The CPAN shell should be able to install most or all of these
for you.
At this point, all of Helios's dependencies should be installed. You can
refer to the GENERIC INSTRUCTIONS to finish installing Helios.