How to Install Quattor with SCDB

Table of Contents

1. Web Server Installation
   1. Apache Recommended Settings
2. Subversion Server
   1. Subversion installation
   2. Apache for subversion and package service
   3. Repository configuration
3. DHCP and TFTPD installation
4. Quattor Server
5. SCDB Initialization
6. Site Configuration
   1. RPM Repositories
   2. Basic System Configuration
   3. Middleware Configuration
7. Cluster Configuration
   1. Hardware description
   2. Adding Machine to pro_site_database.tpl
   3. Creating Machine Profile
8. Quattor Server Final configuration
   1. Installation of hook script and server script
   2. Creation of Ssh Keys
   3. Post-installation CGI Script
   4. Configuration of AII
9. Compiling and Deploying
10. Troubleshooting Initial Installation
    1. Deployment doesn't work

Note : the installation process described below is as generic as possible, but does also contains a set of commands that have been tested only on Scientific Linux version 4. They may need to be modified for other plateforms.

Web Server Installation

The Quattor server needs to run a Web server to serve profiles, kickstart configuration files and execute the CGI script at end of installation to change PXE boot to local disk. In addition, it is recommended (but not necessary) to use this Web server for serving RPMs.

Web server installation requires nothing specific, just the configuration of a document root with enough space if you plan to serve RPMs and the configuration of CGIs. This Web server can be shared with other usages and you can use a specific virtual host instead of a dedicated server.

Apache is the recommended Web server (installation instructions here refer to Apache) and it can be installed from the OS distribution. Note that for subversion http mode, Apache version 2 or above is needed.

Apache Recommended Settings

SCDB has no strong requirement concerning Apache configuration. It generally uses 3 distinct URLs for 3 different purposes :

• Profiles : machine profiles are served by one specific URL shared by all machines. The files there are XML files produces by the PAN compiler when executing ant deploy.
• Kickstart configuration files : this URL is used to store the Kickstart configuration file for each machines. These files are produced by aii-shellfe --configure.
• RPM packages : RPMs are grouped in repositories, each repository has its own URL. This is a common setting to have one common parent URL for all repositories but this is not at all a requirement.

Recommended setting for these 3 areas are :

• Restrict access to profile and Kickstart configuration to IP adresses (or subnets) matching Quattor clients, as these files may contain sensitive information like encrypted passwords or MySQL passwords (cleartext).
• Configure all these areas to ignore any index.html file and auto-indexing. This is particularly important for RPM repositories URLs, as presence of an index.html will prevent SCDB tools to get the list of RPMs in the repository. Recommended settings for these areas are :

      Options Indexes
      DirectoryIndex VeryUnlikelyDirectoryIndex.none
      AllowOverride None
  

Subversion Server

There is no need for a Subversion server dedicated to Quattor. SCDB is just one repository from the Subversion point of view. If you already run a Subversion server, you can skip the installation part and go directly to the configuration part.

Subversion installation

There are many possible installation options for a Subversion server. The best is to install it as Apache module, anyway. There is no requirement for the Subversion server to run on a Linux machine, even if it is the installation option documented here. You can even choose to use a Subversion server outside of your site, if you think the network connection is good enough.

If you need to install a Subversion server, the easiest is to install Apache and then retrieve the RPMs for Subversion from ​Subversion site. Don't forget to install the Apache module which is in a separate RPM.

After installing, you have to configure the Subversion server. Look at Quattor installation guide on ​Quattor web site.

Quick setup:

# Create SVN repository
mkdir -p /var/svn/quattor
svnadmin create /var/svn/quattor
# Fetch the quattor specific post-commit hook
wget  --no-check-certificate "https://trac.lal.in2p3.fr/Quattor/browser/trunk/src/hooks/post-commit?format=raw" -O /var/svn/quattor/hooks/post-commit
# Quattor deployment scripts (used by post-commit svn hook)
mkdir -p /root/quattor/scripts
wget  --no-check-certificate "https://trac.lal.in2p3.fr/Quattor/browser/trunk/src/hooks/build-tag.pl?format=raw" -O /root/quattor/scripts/build-tag.pl

The post-commit file have to be edited. In particular, check for: QUATTORSRV, DEPLOYSCRIPT, MAILER/SVNLOOK/SSH and NOTIFY variables (everything should be self-explaining). Note to Michel: toutes les variables à modifier devraient être groupées au début du fichier. Also in post-commit, beware of the regular expression used to match a tag: it may be wrong for you, tune it as needed.

One should also edit build-tag.pl file, look for JAVA_HOME, $repo and $cache.

The SVN repository have to be accessed by http(s): method (not file:), this imply installation and configuration of mod_dav_svn for Apache.

The SVN repository should belong to the identity that run the web server:

chown -R apache:apache /var/svn/quattor

Apache for subversion and package service

Files /etc/httpd/conf.d/subversion.conf and /etc/httpd/conf.d/ssl.conf (if using ssl) have to be edited and configured.

In /etc/http/conf/httpd.conf, you may have to add the following lines to avoid a bug in the http interface of the rpm client.

<IfModule mod_setenvif.c>
  BrowserMatch "rpm/.*" nokeepalive force-response-1.0
</IfModule>

Repository configuration

For Quattor, you need to create a repository with the standard structure inside it (or inside a branch) :

• trunk : where you make the changes to your running configuration
• tags : used by SCDB administration tool to do deployment
• branches : for alternative developments

For example:

mkdir toto
cd toto
mkdir scdb
mkdir scdb/trunk
mkdir scdb/tags
mkdir scdb/branches
svn import . https://svn.server.tld/svn/quattor --message 'Initial repository layout'

Then, initial checkout will be:

svn checkout https://svn.server.tld/svn/quattor/scdb

DHCP and TFTPD installation

Install DHCPD and TFTPD server from OS distribution. Do a basic configuration of DHCPD server (name servers...).

Template for dhcp configuration can be found in aii-server package, under /usr/share/doc/aii-1.0.44/eg/dhcpd.conf.

Template for tftpd configuration (by xinetd at /etc/xinetd.d/tftp) can be found in aii-server package, under /usr/share/doc/aii-1.0.44/eg/tftp.example.

Note that prefered location for quattor tftp installation is /osinstall/nbp, but it should work under /tftpboot as well.

Quattor Server

In addition to the base system installation, you need to install the following RPMs on a Quattor server where you want to use SCDB :

• Java VM > 1.5.0
• Subversion client (preferably > 1.4)
• cdb-sync
• ncm-template
• aii-server

All but Java and SVN client can be download from ​http://quattorsrv.lal.in2p3.fr/packages/quattor/sl. Always use the last version, unless explicitly mentionned. You can also use APT or YUM from ​http://quattorsw.web.cern.ch/quattorsw/software/quattor.

SCDB Initialization

To start with SCDB, you first need to install a ​Subversion server, an open source product. The http based repository access must be used for quattor, the standalone access wont work (limitation of the build script).

After you have a Subversion server installed, you need to :

• Create a Subversion repository that will be used for SCDB, if it doesn't exist yet, and associate this repository with a URL (this can involve modifying Apache configuration). There is no need to use a dedicated repository. E.g. : http://svn.example.org/Quattor.
• Create a branch in this repository where SCDB will be stored, if the repository is not dedicated to SCDB. E.g. : http://svn.example.org/Quattor/CDB.
• In this branch, create 2 branches trunk and tags (tags is managed by SCDB tools, all the actions you'll do later will be done in trunk. You can also create other branches for your conveniences (like branches but they are not used by standard tools).
• Choose the QWG templates version that suit your needs and import SCDB base and QWG templates in directory that will become you working area. See QWG download for detailed instructions. The easiest is to download and use check-compile.sh (use option -h to get the list of available options). For example, assuming you want to create a cdb sub-directory of your current directory and download QWG templates gLite-3.0.2-10 :

  check-compile.sh -d cdb /templates/tags/gLite-3.0.2-10
  

• Change current directory to the working area, for example :

  cd cdb
  

• Checkout SCDB trunk (empty) in your SCDB working directory :

  svn co http://svn.example.org/Quattor/CDB/trunk .
  

• Configure the repository to ignore some files produced when compiling, using the following command :

  cat > /tmp/ignore <<EOF
  .settings
  build
  build.saved
  deploy
  quattor.build.properties
  .project
  EOF
  svn propset svn:ignore -F /tmp/ignore .
  svn ci
  

• Add everything to your repository with command :

  svn add *
  

• Commit your vanilla SDCB with :

  svn ci -m 'Create initial SCDB'
  

Site Configuration

After copying the SCDB distribution, you need to create your first site. You can do this by copying sites/example directory and customizing a few templates.

RPM Repositories

To use Quattor, you need to deploy software repositories. Even if you want to customize it later, you are probably better to start with a configuration similar to what is provided in repository directory of sites/example directory. You can retrieve an initial directory content for each RPM repository by downloading the contents of the URL specified in comments at the beginning of each repository templates.

Basic System Configuration

Basic system configuration (network parameters, DNS servers, ...) are grouped in template pro_site_cluster_info.tpl in site directory of your site. Look at comments to understand what you need to modify.

Middleware Configuration

Middleware configuration is located in template pro_lcg2_config_site.tpl in site directory of your site. Look at comments to understand what you need to modify.

Cluster Configuration

After creating your site, you need to create your first cluster. You can do this by copying clusters/example directory and customizing a few templates.

Hardware description

You need to create a template describing the hardware configuration of your machines. This is generally placed in hardwaresub-directory of site directory. Look at examples.

Adding Machine to pro_site_database.tpl

Before being able to configure the machine, you need to create an entry for the machine name in both tables of pro_site_database.tpl. First entry defines the address associated with the machine name, second entry defines the hardware template associated with the machne.

Creating Machine Profile

Copy an existing profile in examples corresponding to the machine type you want to create.

Quattor Server Final configuration

Before being able to deploy the created configuration, there is a last configuration step needed to allow deployment of the configuration after successful compilation. This involves :

• Adding a hook script to the Subversion repository to trigger the deployment
• Adding a script on the Quattor server that will be launched by the hook script, using ssh
• Configuring SSH keys to allow execution of the previous script as root (preferably) from the Apache account
• Add a CGI script on Quattor server used at end of installation of a machine to allow next boot from local disk.
• Configuration of AII

Installation of hook script and server script

The hook script, post-commit, is provided as part of SCDB, in the src/hooks directory. It must be installed on your Subversion server, in the hook directory of the repository, and given executable permission for Apache user. This script requires a configuration file /etc/quattor-deploy.conf, see SCDB server-side customizations for details.

The other script, build-tag.pl, also provided as part of SCDB, in the src/hooks directory, must be installed (root executable) in /root/quattor/scripts on the Quattor server.

build-tag.pl requires file quattor.build.properties to be created in /root/quattor. A template of this file is available in SCDB distribution, in src/hooks directory. It must be edited to reflect your local configuration.

For more details about these scripts and their customization, see the page on SCDB server-side customizations.

Creation of Ssh Keys

Currently, deployment of new version of the templates is done by the hook script triggered by ant deploy executing the server script build-tag.pl through ssh. There is no way to enter a password at this time, thus ssh must be configured in such a way that the Apache account on the Subversion server can do a ssh connection as root on the Quattor server, without password. The easiest is to use ssh keys to do that.

Post-installation CGI Script

At the end of a machine installation, as part of the Kickstart post-intallation script, a CGI script is executed on the Quattor server to change PXE configuration in order for the machine to boot from local disk next time. This allows to set PXE as the first boot device in the BIOS and control re-installation via aii-shellfe command.

This script, aii-installack.cgi, can be found in SCDB directory src/cgis. It must be placed on the Web server running on the Quattor server, in the directory for CGIs.

The apache server must be able to run that script as root. Best is to have sudo installed and use visudo to add the following to /etc/sudoers: apache sbgat419.in2p3.fr=(ALL) NOPASSWD: /usr/sbin/aii-shellfe

Configuration of AII

This involves 2 separate steps :

• Customization of /etc/aii*.conf files
• Customization of AII related variables in templates

To customize AII configuration files, located in /etc and named aii-*.conf, refer to the comment in each files. Main parameters to customize are the URL to use to download profiles (in aii-shellfe.conf) and the directory where to place kickstart configuration files produced by AII (in aii-osinstall.conf).

There are a few variables to customize in site templates to reflect your Quattor and AII configuration, mainly :

• QUATTOR_PROFILE_URL : URL to use to download machine profiles.
• AII_OSINSTALL_SRV : Name of the Web server serving kickstart configuration files and RPMs.
• AII_ACKSRV : Name of the Web server to use for the post-installation CGI. Defaults to AII_OSINSTALL_SRV
• AII_ACKCGI : post-installation CGI URL. Defaults to /cgi-bin/aii-installack.cgi.
• AII_OSINSTALL_TEMPLATE : name of the Kickstart configuration template to use. Defaults to i386_sl3_ks.conf.

These variables are generally defined site-wide, in the template pro_site_global_variables.tpl located in site directory. Look at provided examples, in SCDB distribution.

Compiling and Deploying

After the configuration is finished, you can try to compile your first profile, deploy it and install the machine. This involves the following steps :

• In SCDB (working area copy) top level directory :
  • Update of RPM repository templates :

    external/ant/bin/ant update.rep.templates
    

  • Profile compilation and deployment (deployment will not occur until compilation succeds) :

    external/ant/bin/ant deploy
    

• On the Quattor server :
  • Creation of Kickstart configuration file for the machine :

    aii-shellfe --configure your.machine.domain
    

  • Update of DHCP and PXE for the machine to be installed at next boot :

    aii-shellfe --install your.machine.domain
    

Troubleshooting Initial Installation

Deployment doesn't work

Look at SCDB ​server-side customizations page.