Here are the steps I've used for installing the Zend Server PE version of php on the redhat el 5.3/5.4 machines...

For the curious, more info about Zend Server at: http://www.zend.com/en/products/server/editions

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:: STEP 1 (optional) ::  if php has been installed already, remove (yum erase) all php-related packages

e.g. standard php installation:
# yum erase `yum list | grep php | grep installed | cut -f1 -d. | tr '\n' ' '`

e.g. upgrading from zend server 4:
# zendctl.sh stop; yum erase `rpm -qa | grep zend | xargs`
# for i in `ipcs -m |grep -v Shared | grep -v shmid | awk -F " " '{print $2}'` ; do ipcrm -m $i; done
# rm `find /tmp -user apache | xargs`
# rm -r /usr/local/zend

:: STEP 2 :: set up Zend package repository

# vi /etc/yum.repos.d/zend.repo
[Zend]
name=Zend Server
baseurl=http://repos.zend.com/zend-server/rpm/$basearch
enabled=1
gpgcheck=0
 
[Zend_noarch]
name=Zend Server - noarch
baseurl=http://repos.zend.com/zend-server/rpm/noarch
enabled=1
gpgcheck=0


:: STEP 3 :: install ZS PE basics, extras (note: if you don't have apache installed, this will install the stock redhat apache as a prereq)

To install Zend Server with PHP 5.2 run:
# yum install zend-server-php-5.2
# yum install php-5.2-extra-extensions-zend-server php-5.2-source-zend-server
# yum clean all

To install Zend Server with PHP 5.3 run:
# yum install zend-server-php-5.3
# yum install php-5.3-extra-extensions-zend-server php-5.3-source-zend-server
# yum clean all


:: STEP 4 :: make sure the php binaries and apache module can find the ZS PE libraries

# vi /etc/ld.so.conf.d/zend-platform.conf
	/usr/local/zend/lib
# ldconfig

You can ignore a warning of: "ldconfig: /usr/local/zend/lib/libming.so.0 is not a symbolic link"

:: STEP 5 :: set up log rotation for ZS PE logs

# vi /etc/logrotate.d/zendserver
/usr/local/zend/var/log/*.log {
       size 5M
       missingok
       rotate 10
       compress
       delaycompress
       copytruncate
}


:: STEP 6a (optional) :: If ldaps connectivity is needed (e.g. GTED), you have
to manually fix the ldap module that ships with ZS. Fortunately this is
simple...

# yum install openldap-devel

# cd /usr/local/zend/share/php-source/ext/ldap
# /usr/local/zend/bin/phpize
# ./configure --with-php-config=/usr/local/zend/bin/php-config --with-ldap-sasl
# make
# make install


:: STEP 6b (optional) :: If ssl connectivity to postgreSQL databases is needed (e.g. to MAGE), you have to manually fix the pgsql and/ or the pdo_pgsql modules as well...

# yum install postgresql-devel openssl-devel

# cd /usr/local/zend/share/php-source/ext/pgsql
# /usr/local/zend/bin/phpize
# ./configure --with-php-config=/usr/local/zend/bin/php-config
# make
# make install

# cd /usr/local/zend/share/php-source/ext/pdo_pgsql
# /usr/local/zend/bin/phpize
# ./configure --with-php-config=/usr/local/zend/bin/php-config --with-pdo-pgsql=/usr/bin/pg_config
# make
# make install


:: STEP 6c (optional) :: If ssl connectivity with curl is needed, you have to manually fix the curl module as well...

# yum install libidn libidn-devel curl curl-devel
# cd /usr/local/zend/share/php-source/ext/curl
# /usr/local/zend/bin/phpize
# ./configure --with-ssl
# make
# make install


:: STEP 7 :: restart ZS PE... the first time it starts after install, it doesn't load all the modules

# /usr/local/zend/bin/zendctl.sh restart


:: STEP 8 (optional) :: Reset ZS PE admin password

# /usr/local/zend/bin/gui_passwd.sh


:: STEP 9 (optional) :: further configuration of ZS PE can be done via web browser at http://host:10081/ or https://host:10082/  ... though the default should be find for most sites.

Notable things I change/fix:

shell on the box:
   mkdir /var/run/php-sessions
   chown apache:apache /var/run/php-sessions

in the admin interface:
- correct path to sendmail ( /usr/lib/sendmail -t -i )
- sessions settings: http only, session save path (stop polluting /tmp)
   session.cookie_httponly On
   session.cookie_secure On   (only if no http sessions will be used)
   session.hash_function SHA-1 (160 bits)
   session.save_path /var/run/php-sessions/
   session.use_only_cookies On

:: STEP 10 (optional) :: if you are big into configuring ZS PE in step 9 and want to use your own cert for the :10082 server instead of a self-signed one, you can

1) create a pem file of your server's key and cert file (just concatenate them)
2) edit /usr/local/zend/gui/lighttpd/etc/lighttpd.conf ... here the example is for faux.oit.gatech.edu, which has a GTCA signed cert (thus the need for the ssl.ca-file line):

 $SERVER["socket"] == ":10082" {
  ssl.engine = "enable"
  ssl.pemfile="/etc/pki/tls/private/faux.oit/server.pem"
  ssl.ca-file="/etc/pki/tls/certs/gtroot.pem"
  server.name="faux.oit.gatech.edu"
 }

3) make sure to restart (as in step 7 above)


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