Apache

I've noticed these in httpd access log starting with Apache2.2:

The apache server occasionally hits localhost to signal its children. See the apache wiki for more info.

"When Apache HTTP Server manages its child processes, it needs a way to wake up processes that are listening for new connections. To do this, it sends a simple HTTP request back to itself...
These requests are perfectly normal and you do not, in general, need to worry about them. They can simply be ignored."

Unfortunately, the homepage I host is a dynamic one and this becomes very costly during busy times. I see a large number of those internal dummy connection requests during an apache graceful restart (SIGUSR1) and at the same time the cpu load on the Apache2.2 server maxes out at nearly 100%. I do not see this cpu load during a graceful restart on apache 2.0 httpd servers.

With the below mod_rewrite rule in place I was able to reduce the load by pointing http request coming from HTTP_USER_AGENT, "internal dummy request" to an empty static html page.

Also, removed logging of such requests via:

As of this writing, the latest versions were:

• apache_1.3.41
  
• php-4.4.8
  
• openssl-0.9.8g
  
• mod_ssl-2.8.31-1.3.41

Once the files are downloaded and extracted; config, compile and install in the below order:

1. Install openssl:
   
   $ ./config --prefix=/usr/local --openssldir=/usr/local/openssl
$ make
# make install

2. mod_ssl patch:
   
   $ ./configure \
--with-ssl=../openssl-0.9.8g \
--with-apache=../apache_1.3.41

3. Pre-configure apache:
   
   $ ./configure

4. Install php:
   
   $ ./configure \
--with-gd \
--with-jpeg-dir \
--with-png-dir \
--with-zlib-dir \
--with-freetype \
--with-freetype-dir=/usr/lib \
--enable-gd-native-ttf \
--enable-memory-limit \
--with-ldap \
--with-mysql \
--with-apache=../apache_1.3.41
$ make
# make install

5. Install apache
   
   $ SSL_BASE=../openssl-0.9.8g \
./configure \
--prefix=/usr/local/apache \
--enable-module=rewrite \
--enable-module=so \
--activate-module=src/modules/php4/libphp4.a \
--enable-module=ssl

1. Download and unpackage the source files:
   
   $ cd /usr/local/src
$ wget http://www.ibiblio.org/pub/mirrors/apache/httpd/apache_1.3.41.tar.gz
$ wget http://us2.php.net/get/php-4.4.8.tar.gz/from/us.php.net/mirror
$ tar -xvzf apache_1.3.41.tar.gz
$ tar -xvzf php-4.4.8.tar.gz

2. Preconfigure apache:
   
   $ cd apache_1.3.41
$ make clean
$ ./configure

3. Configure, compile, install php:
   
   $ cd ../php-4.4.8
$ make clean
$ ./configure \
--with-gd \
--with-jpeg-dir \
--with-png-dir \
--with-zlib-dir \
--with-freetype \
--with-freetype-dir=/usr/lib \
--enable-gd-native-ttf \
--enable-memory-limit \
--with-ldap \
--with-mysql=/usr/local/mysql \
--with-apache=../apache_1.3.41
$ make
# make install

4. Configure, compile, install apache:
   
   $ ./configure \
--prefix=/usr/local/apache \
--enable-module=rewrite \
--enable-module=so \
--activate-module=src/modules/php4/libphp4.a
$ make
# make install

Recently a particular folder in a site started coming up with blank php pages and the root cause being Segmentation fault after memory exhaustion. The subfolder contents would only come up after doing a restart of apache.

So something tried to access a region of memory that it did not have rights to. May be due to either bad RAM, or a code problem.

My first instinct was eAccelerator as I had done a recent php update and had not re-compiled it.

I still had the same issue the next day and bumped up the memory_limit from 16M to 32M in php.ini and from 32M to 64M in eaccelerator.ini .

These are some notes I had taken down during the installation of Bugzilla on a server with ISPConfig hosting control panel:

Requirements:

Create Site:

Site was created via the ISPConfig control panel with "web6_bugs" as the admin user and "web6" as the group.

Install:

Apache with mod_perl need the below directives in httpd.conf:

Runs a lot faster, but is a memory hog. Suggested to turn off KeepAlive in apache when running mod_perl.

Crontab Entry:

Latest Compile with pdo drivers for mysql along with mod_security.

NOTE:
Remove the MySQL-shared rpm else openssl will not work.

The acronym LAMP refers to a set of free software programs commonly used together to run dynamic Web sites or servers

Linux, the operating system;

Apache, the Web server;

MySQL, the database management system (or database server)

Perl, PHP, and/or Python, scripting languages

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