Here are the steps needed to install the latest version of APC (3.1.8 at the time of writing this article; please check for the latest version available when you are reading this and make the changes accordingly):
cd /usr/local/src
wget http://pecl.php.net/get/APC-3.1.8.tgz
tar -zxvf APC-3.1.8.tgz
cd APC-3.1.8
phpize
./configure --enable-apc --enable-apc-mmap --with-apxs --with-php-config=/usr/local/bin/php-config
make
make install

Next, activate the apc module in php.ini by adding something like this:
extension="apc.so"
apc.enabled=1
apc.shm_segments=1
apc.shm_size=128

Finally, you will have to restart apache and after that the APC module should be activated and in use. Hopefully, this will help you enable APC on your CPanel server in some very simple steps in less that 5minutes.

Server: Locate sftp-server binary and add to your list of valid shells on the system.

which sftp-server

Note:   This will most likely give you this: /usr/libexec/openssh/sftp-server

echo /usr/libexec/openssh/sftp-server >> /etc/shells

Note:  You may want to backup your /etc/shells first

User Accounts:  Add or modify accounts to use sftp-server.

New User

useradd -s /usr/libexec/openssh/sftp-server  sftponlyuser

Note:  Important parameter there is the “-s /usr/libexec/openssh/sftp-server”, which sets the default shell for this account.   By default you will have “/bin/bash”.

Existing User:

vi /etc/passwd

Find the user that you want to configure for sftp only access and edit its shell.  For exampleyou will see a line “username:x:500:500::/home/username:/bin/bash” change “/bin/bash” to “/usr/libexec/openssh/sftp-server” and save.  Note: You may want to backup your /etc/passwd file as well.

Let’s assume you already moved the databases (separate database for Drupal and CiviCRM as a recommended setup) and the files to new location and have set the correct file permissions as well. Here is the part that you need for your CiviCRM to work on new location and domain:

• access your database and empty civicrm.domain:config_backend. You see this anywhere with CiviCRM guide.
• update database details, site path/directory, and domain on civicrm.settings.php
• emtpy sites/default/files/civicrm/template_c (or make this entire dir writable by web user)
• login to you new Drupal site and visit these urls:
  http://sitename/civicrm/menu/rebuild?reset=1
http://sitename/civicrm/admin/setting/updateConfigBackend?reset=1
  Note: This will rebuild the settings for you – if not, repeat/review all the above steps.

Environment: Ubuntu 10.10, Apache, PHP, MySQL, Drupal 6.20

Things to install / setup: Solr, Tomcat6, ApacheSolr module for Drupal, and SolrPHPClient library

1.) Install Tomcat and setup your Tomcat admin user.

aptitude install tomcat6 tomcat6-admin tomcat6-common tomcat6-user
vi /etc/tomcat6/tomcat-users.xml
<role rolename=”admin”/>
<role rolename=”manager”/>
<user username=”tomcat” password=”password” roles=”admin,manager”/>
/etc/init.d/tomcat6 restart

If all is good you will be able to access Tomcat admin at http://hostname:8080. Default page will show with links to admin section, etc.

2.) Install Solr

wget http://apache.rediris.es/lucene/solr/1.4.1/apache-solr-1.4.1.zip (check for updates)
unzip apache-solr-1.4.1.zip
mkdir /usr/share/tomcat6/webapps
cp apache-solr-1.4.1/dist/apache-solr-1.4.1.war /usr/share/tomcat6/webapps/solr.war
cp -r apache-solr-1.4.1/example/solr /usr/share/tomcat6/solr
vi /etc/tomcat6/Catalina/localhost/solr.xml
<Context docBase=”/usr/share/tomcat6/webapps/solr.war” debug=”0″ privileged=”true” allowLinking=”true” crossContext=”true”>
<Environment name=”solr/home” type=”java.lang.String” value=”/usr/share/tomcat6/solr” override=”true” />
</Context>
chown -r tomcat6.tomcat6 /var/lib/tomcat6
/etc/init.d/tomcat6 restart

You should see Solr access on your Tomcat admin/manager page (http://hostname:8080/manager/html).

3.) Connect Drupal Site to Solr (multi-core setup)

I already have a Drupal site with ApacheSolr module installed and SolrPHPclient library.

cp /path/drupal_site/sites/all/modules/apachesolr/schema.xml /usr/share/tomcat6/solr/conf/schema.xml
cp /path/drupal_site/sites/all/modules/apachesolr/solrconfig.xml /usr/share/tomcat6/solr/conf/solrconfig.xml
cp apache-solr-1.4.1/example/multicore/solr.xml /usr/share/tomcat6/solr/
mkdir /usr/share/tomcat6/solr/site_sample1
cp -r /usr/share/tomcat6/solr/conf /usr/share/tomcat6/solr/site_sample1/conf
vi /usr/share/tomcat6/solr/solr.xml
<core name=”site1″ instanceDir=”site_sample1″ />
chown -R tomcat6:root /usr/share/tomcat6/solr/
/etc/init.d/tomcat6 restart

Visit ApacheSolr settings of your Drupal admin and enter the configuration:
Solr Hostname: localhost
Solr Port: 8080
Solr Path: /solr/site1

To add new site to Solr:
mkdir /usr/share/tomcat6/solr/site_sample2
cp -r /usr/share/tomcat6/solr/conf /usr/share/tomcat6/solr/site_sample2/conf
vi /usr/share/tomcat6/solr/solr.xml
<core name=”site2″ instanceDir=”site_sample2″ />

That’s All.

Configure Cpanel for SVN
Recompile Apache/PHP (WHM -> Software -> EasyApache) and enable support for the following:

• Dav (Among other things mod_dav can be used by DAV enabled Frontpage clients instead of FP extensions)
• BerkeleyDB. Note: BerkeleyDB support (“–with-berkeley-db“) is not enabled by default in EasyApache so you need to add this manually to your EasyApache config using this guide or this one.

Install Subversion and mod_dav_svn
Install subversion using yum (yum install subversion) or install it from source. At this time CentOS repo version is 1.4.x and the latest from source is 1.6.x.

Install and enable mod_dav_svn in Cpanel
Install mod_dav_svn using yum (yum install mod_dav_svn) – version 1.4.x same as subersion above.
Load mod_dav_svn module to Apache. Go to WHM -> Service Configuration -> Apache Configuration -> Include Editor -> Pre-Main Include. Select either “All Versions” or your current Apache version (ex: “2.2.16“) from drop-down list. Or you can edit their corresponding file directly:
All Versions: /usr/local/apache/conf/includes/pre_main_global.conf
Apache 2.2.16: /usr/local/apache/conf/includes/pre_main_2.conf
Add the codes below and click “Update” button to save config. This will restart Apache if no error on your configuration.
<IfModule mod_dav.c>
LoadModule dav_svn_module /usr/lib/httpd/modules/mod_dav_svn.so
LoadModule authz_svn_module /usr/lib/httpd/modules/mod_authz_svn.so
</IfModule>

Create repository and add http access (ex: http://domain.com/svn)
Create your repository: svnadmin create /path/to/svn/repos
Add the code below to your domain’s custom include file. You need to create this file based on this guide to preserve when you recompile Apache/PHP.
Example file (Apache2,standard/non-ssl): /usr/local/apache/conf/userdata/std/2/cpanl_user/domain.com/svn.conf
File Contents:
<Location /svn>
#  mod dav svn support and location of svn repo files
DAV svn
SVNPath /path/to/svn/repos
# authentication for security, create using htpasswd
AuthType Basic
AuthName "SVN Access"
AuthUserFile /path/to/file/containing/user.pass
Require valid-user
# added for permissions/access
Order allow,deny
Allow from all
</Location>

Detailed Setup:

• Drupal 6.19
• ApacheSolr module 6-1.1
• Apache Solr PHP Client Library: Rev.22
• Solr 1.4.1
• Tomcat 6.0.29
• SunJDK 6update21
• RHEL5.5×64

Install Process: Tomcat

• Create solr user
• Download Tomcat6
• Extract to /opt/tomcat  **this will be the $CATALINA_HOME directory, you can use any dir you want
• Edit /opt/tomcat/conf/tomcat-users.xml to enable Tomcat login.  See comments in this file.

<role rolename="manager"/>
<role rolename="admin"/>
<user username="tomcat" password="tomcat" roles="manager,admin"/>

• Test run your Tomcat:  /opt/tomcat/bin/catalina.sh run. Chown all Tomcat files to solr user (chown -R solr.solr /opt/tomcat). Default server setting will use port 8080, to customized edit the file /opt/tomcat/conf/server.xml. If you encounter error on “BASEDIR environment variable is not defined correctly…“, check permissions of .sh files inside /opt/tomcat/bin/ and make them executable (chmod 755 /opt/tomcat/bin/*.sh).
• Add startup (init) script. Copy this Tomcat6 init file from Apache.org to /etc/init.d/tomcat6.  Check and update variables like Java home, Tomcat directory, etc, if needed. Add to startup /sbin/chkconfig --add tomcat6 and /sbin/chkconfig tomcat6 on. Dependencies: redhat-lsb (or lsb-base?)
• Visit your Tomcat Admin page. ex http://localhost:8080

Install Process: Solr

• Download Solr
• Extract to temporary location, ex: /opt/apache-solr-1.4.1
• Copy /opt/apache-solr-1.4.1/dist/apache-solr-1.4.1.war to /opt/tomcat/webapps/solr.war
• Copy /opt/apache-solr-1.4.1/example/solr directory to /opt/tomcat/solr  **this will be the $SOLR_HOME directory, you can use any dir you want
• Create file /opt/tomcat/conf/Catalina/localhost/solr.xml with the following configuration.  Make sure paths are correct.

<Context docBase="/opt/tomcat/webapps/solr.war" debug="0" privileged="true" allowLinking="true" crossContext="true">
<Environment name="solr/home" type="java.lang.String" value="/opt/tomcat/solr" override="true" />
</Context>

Install Process: ApacheSolr Drupal module and SolrPHP client

• Install/enable Drupal ApacheSolr module. Drush, CVS, or traditional install – whatever you want.  Example: /var/www/site1/sites/all/modules/apachesolr
• Download SolrPHP client library

Configure Solr for Multi-Core Setup

• Copy /var/www/site1/sites/all/modules/apachesolr/schema.xml to /opt/tomcat/solr/conf/schema.xml
• Copy /var/www/site1/sites/all/modules/apachesolr/solrconfig.xml to /opt/tomcat/solr/conf/solrconfig.xml
• Copy /opt/apache-solr-1.4.1/example/multicore/solr.xml to /opt/tomcat/solr/solr.xml
• Create directory for each site and copy /opt/tomcat/solr/conf directory to each of them. Example:

mkdir /opt/tomcat/solr/site1
mkdir /opt/tomcat/solr/site2
cp -r /opt/tomcat/solr/conf /opt/tomcat/solr/site1/
cp -r /opt/tomcat/solr/conf /opt/tomcat/solr/site2/

• Edit /opt/tomcat/solr/solr.xml with the following config:

<?xml version="1.0" encoding="UTF-8" ?>
<solr persistent="false">
<cores adminPath="/admin/cores">
<core name="site1" instanceDir="site1" />
<core name="site1" instanceDir="site2" />
</cores>
</solr>

• Start or Restart Tomcat: /etc/init.d/tomcat6 start
• Visit http://localhost:8080/ and go to you Solr App

Configure Drupal site:

• Go to ApacheSolr settings http://localhost/admin/settings/apachesolr
• Save your config and if all is good you’ll see message: Your site has contacted the Apache Solr server.

Solr host name: localhost
Solr port: 8080
Solr path (for site1): /solr/site1


• Configure your search index.

Usefull when transferring files between servers where you only have ftp access.

Update:
Need to install GeoTrust’s intermidiate CA.

• System Engineering – Systems engineering is an interdisciplinary field of engineering that focuses on how complex engineering projects should be designed and managed
• Fault Tolerance – looking at massive
• Control Systems Engineering
• Max users on apache or max connections to your db – Sheer Pin -

Interesting  which arent about the web but relate to Systems Enge

• Complex Systems Fail in Funny Ways – Accidents, Living with High-Risk Technologies
• An Engineers view of Human Error – Human Error comes in different flavors
• RAD Lab

Why do systems engineers have it easy?

• No one dies when the site goes down
• If we make a mistake we can recover quickly
• Future is bright

John concludes in these calls to actions:

• Look around!  NASA, go to non web conferences that relate, for example, systems safety
• Engage Academia
• It’s time for our field to get more sophisticated