Cannot load /etc/httpd/modules/mod_wl_24.so into server: libopmnsecure.so: cannot open shared object file: No such file or directory

Issue Definition:-

  ==> All plugin files are copied to the apache module folder /etc/httpd/modules

  ==> In httpd.conf below line is added

    LoadModule weblogic_module  /etc/httpd/modules/mod_wl_24.so

  ==> Below issue occurs while loading WebLogic Pxoy Plugin 12.2.1.2.0  

          While executing "httpd -t"  OR "./apachectl -t"

[root@test2 conf]# httpd -t
httpd: Syntax error on line 60 of /etc/httpd/conf/httpd.conf: Cannot load /etc/httpd/modules/mod_wl_24.so into server: libopmnsecure.so: cannot open shared object file: No such file or directory
[root@test2 conf]#

Cause:-

 This issue occurs because link to shared library are not present

Solution :-

  a) Edit the file ld.so.conf by adding plugin module path /etc/httpd/modules

   vi /etc/ld.so.conf

   /etc/httpd/modules



  b) Execute below command

   ldconfig

  c) Now test the httpd syntax check.

   httpd -t  OR ./apachectl -t 




It Works!


For more information click on the link: http://www.cprogramming.com/tutorial/shared-libraries-linux-gcc.html

How To Rotate Apache error_log & access_log Logs?

There are two methods available for rotating Apache Httpd Server logs.

     1) Manual Log Rotation
     2) Log Rotation Using Piped Logs OR rotatelogs Utility

Method 1)  Manual Log Rotation 

By using a graceful restart, the server can be instructed to open new log files without losing any existing or pending connections from clients. However, in order to accomplish this, the server must continue to write to the old log files while it finishes serving old requests. It is therefore necessary to wait for some time after the restart before doing any processing on the log files

a) Rename access_log & error_log

  cd /etc/httpd/logs
  mv access_log access_log.old
  mv error_log error_log.old



b) Do the graceful restart of Apache & check whether new log files error_log & access_log generated or not.

  service httpd graceful



c) Zip old log files after some time because existing instructions are writing to old files.

  sleep 600
  gzip access_log.old error_log.old




For More Information Please refer link: https://httpd.apache.org/docs/2.4/logs.html#rotation

Method 2) Log Rotation Using  rotatelogs Utility (Piped Logs Method)

Apache httpd is capable of writing error and access log files through a pipe to another process, rather than directly to a file. In order to write logs to a pipe, simply replace the filename with the pipe character "|", followed by the name of the executable which should accept log entries on its standard input. The server will start the piped-log process when the server starts, and will restart it if it crashes while the server is running.

One important use of piped logs is to allow log rotation without having to restart the server. The Apache HTTP Server includes a simple program called rotatelogs for this purpose.


Syntax:

rotatelogs [ -l ] [ -L linkname ] [ -p program ] [ -f ] [ -t ] [ -v ] [ -e ] [ -c ] [ -n number-of-files ] logfile rotationtime|filesize(B|K|M|G) [ offset ]


To know more about Options click on link https://httpd.apache.org/docs/2.4/programs/rotatelogs.html

Example 1: Below option rotates access_log every 2 minutes (you can set your own time value) & create log file in the format access_log.yyyy.mm.dd.HH.MM

CustomLog "|/usr/sbin/rotatelogs /etc/httpd/logs/access_log.%Y.%m.%d.%H.%M 120" combined

Example 2: Below option rotates error_log for every 4KB (you can set your own size value).

ErrorLog "|/usr/sbin/rotatelogs /etc/httpd/logs/error_log.%Y-%m-%d-%H_%M_%S 4K"








For More Information Please Refere below Links:
https://httpd.apache.org/docs/2.4/programs/rotatelogs.html

https://httpd.apache.org/docs/2.4/logs.html#piped


Apache Log Format Common & Combined: https://httpd.apache.org/docs/1.3/logs.html#common

Nginx Reverse Proxy To Apache Http Server

Architecture Diagram 

==========================

Summary:
========

     1) Installing Nginx
     2) Installing Apache Http Server & Integrating With Tomcat Application Server
     3) Integrating Nginx with Apache Http Server
     4) Start the Nginx Server
     5) Testing the setup Using Nginx URL.


Steps
=====

1) Installing Nginx

Download Nginx Source Files using below URL

http://nginx.org/download/nginx-1.10.1.tar.gz

OR

https://www.nginx.com/resources/wiki/start/topics/tutorials/install/

Copy the File nginx-1.10.1.tar.gz to Remote Machine 192.168.52.129 using WinSCP



Untar the File nginx-1.10.1.tar.gz using below Command.

tar -zxvf nginx-1.10.1.tar.gz

Navigate to newly create directory ie. /root/nginx/nginx-1.10.1  & Run below Commands.

For more "Installation and Compile-Time Options" Please refer below link.

https://www.nginx.com/resources/wiki/start/topics/tutorials/installoptions/

cd /root/nginx/nginx-1.10.1

./configure --with-openssl=/usr/lib64/openssl

make 

make install


Configuration summary

==================

  + using system PCRE library

  + using OpenSSL library: /usr/lib64/openssl

  + using builtin md5 code

  + sha1 library is not found

  + using system zlib library

  nginx path prefix: "/usr/local/nginx"

  nginx binary file: "/usr/local/nginx/sbin/nginx"

  nginx modules path: "/usr/local/nginx/modules"

  nginx configuration prefix: "/usr/local/nginx/conf"

  nginx configuration file: "/usr/local/nginx/conf/nginx.conf"

  nginx pid file: "/usr/local/nginx/logs/nginx.pid"

  nginx error log file: "/usr/local/nginx/logs/error.log"

  nginx http access log file: "/usr/local/nginx/logs/access.log"

  nginx http client request body temporary files: "client_body_temp"

  nginx http proxy temporary files: "proxy_temp"

  nginx http fastcgi temporary files: "fastcgi_temp"

  nginx http uwsgi temporary files: "uwsgi_temp"

  nginx http scgi temporary files: "scgi_temp"

2) Installing Apache Http Server & Integrating With Tomcat Application Server

Please refer below URL for this Task

https://blogbyjagan.blogspot.in/2016/12/apache-tomcat-clustering-with-apache.html


3) Integrating Nginx with Apache Http Server

Navigate to the nginx.conf location

cd /usr/local/nginx/conf

Open the file nginx.conf & add the below content for proxying requests through Apache Webserver

vi nginx.conf

        location /examples {

             proxy_set_header X-Forwarded-Host $host:$server_port;

             proxy_set_header X-Forwarded-Server $host;

             proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

             proxy_store off;

             proxy_buffering off;

             proxy_pass http://192.168.52.161;

        }

4) Start the Nginx Server

cd /usr/local/nginx/sbin

./nginx

Note: Below command is used for stopping Nginx

./nginx -s stop

5) Testing the setup Using Nginx URL.

http://192.168.52.129/examples/

Apache Tomcat Clustering with Apache Http Server

Summary 

     1) Create OS User tomcat
     2) Install the JDK  & Export The JAVA_HOME in .bash_profile
     3) Install Tomcat Binaries in Two Directories instance1 & instance2
     4) Set JAVA_OPTIONS in setenv.sh file
     5) Install Apache Http Server
     6) Compile & Build Tomcat Connector for Generating mod_jk.so
     7) Load the mod_jk.so file in httpd.conf file located at /etc/httpd/conf
     8) Create workers.properties file with below content in Apache WebServer Machine
     9)  Load the worker.properties file & Other Entries in httpd.conf
   10)  Enter application context specific  entries in httpd.conf
   11)  Start up instance1,instance2 and apache WebServer.
   12)  Test the set up using WebServer URL


Steps
=====

1) Create OS User tomcat

     Use below command for creating user & setting password

     useradd -u 54666  tomcat
     passwd tomcat





2) Install the JDK  & Export The JAVA_HOME in .bash_profile

Download JDK using below link

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

Use below command for installing jdk

tar -zxvf jdk-8u112-linux-x64.tar.gz



Set JAVA_HOME  by adding below lines in .bash_profile

vi ~/.bash_profile

JAVA_HOME=/home/tomcat/java/jdk1.8.0_112
export JAVA_HOME
export PATH=$JAVA_HOME/bin:$PATH



3) Install Tomcat Binaries & Export The CATALINA_HOME in .bash_profile

Download tomcat 8 using below link

https://tomcat.apache.org/download-80.cgi

Create two directories for two instances say instance1 & instance2

mkdir mkdir instance1 instance2



Install tomcat by executing below command in directories instance1 and instance2

 tar -zxvf apache-tomcat-8.5.9.tar.gz

4) Set JAVA_OPTIONS in setenv.sh file for instance1 & instance2

Create file setenv.sh

cd /home/tomcat/instance1/apache-tomcat-8.5.9/bin
touch setenv.sh

 cd /home/tomcat/instance2/apache-tomcat-8.5.9/bin
touch setenv.sh

Add below content to setenv.sh 

JAVA_OPTS="-Xms256m -Xmx512m "

Note: Java Options PermSize &  MaxPermSize are Deprecated in JDK8

5) Install Apache Http Server

Install Apache WebServer Using below link

https://blogbyjagan.blogspot.in/2015/10/wls-reading.html

OR Use below command for quick installation

yum install httpd

6) Compile & Build Tomcat Connector for Generating mod_jk.so  in Apache webServer Machine.

Download Tomcat Connector using below link

https://tomcat.apache.org/connectors-doc/

Using WinSCP copy the Connector file to the remote machine & untar it



navigate to directory /connector/tomcat-connectors-1.2.42-src/native & execute below command

cd /connector/tomcat-connectors-1.2.42-src/native

./configure --with-apxs=/usr/bin/apxs

make

make install

Now navigate to the directory /connector/tomcat-connectors-1.2.42-src/native/apache-2.0 & copy the mod_jk.so to /etc/httpd/modules

cd /connector/tomcat-connectors-1.2.42-src/native/apache-2.0
cp mod_jk.so /etc/httpd/modules

7) Load the mod_jk.so file in httpd.conf file located at /etc/httpd/conf

LoadModule jk_module        modules/mod_jk.so

8) Create workers.properties file with below content in Apache WebServer Machine

cd /etc/httpd/conf
touch workers.properties

Add below content in workers.properties file and Save & Exit

worker.list=instance1,instance2

worker.instance1.type=ajp13
worker.instance1.port=8009
worker.instance1.host=192.168.52.129

worker.instance2.type=ajp13
worker.instance2.port=8010
worker.instance2.host=192.168.52.129

worker.balancer.type=lb
worker.balancer.balance_workers=instance1,instance2

worker.stat.type=status
worker.list=balancer,stat

worker.ajp13.lbfactor=50
worker.ajp13.cachesize=10
worker.ajp13.cache_timeout=600
worker.ajp13.socket_keepalive=1
worker.ajp13.socket_timeout=300

9) Load the worker.properties file & Other Entries in httpd.conf 

JkWorkersFile /etc/httpd/conf/workers.properties
JkLogFile /etc/httpd/logs/mod_jk.log
JkLogLevel info
JkLogStampFormat "[%a %b %d %H:%M:%S %Y]"
JkOptions +ForwardKeySize +ForwardURICompat -ForwardDirectories
JkRequestLogFormat "%w %V %T"

10)  Enter below application specific  entries in httpd.conf 

JkMount /examples balancer
JkMount /examples/* balancer

JkMount  /status  stat

11) Now login to the tomcat machine & change instance1 and instance2 ports in server.xml file

cd /home/tomcat/instance1/apache-tomcat-8.5.9/conf/
vi server.xml

instance1: tomcat server port 8080, AJP port 8009, shutdown port 8005

cd /home/tomcat/instance2/apache-tomcat-8.5.9/conf/
vi server.xml
instance2: tomcat server port 8081, AJP port 8010, shutdown port 8006

11) Start up instance1,instance2 and apache WebServer.

On Tomcat Machine
==================
[tomcat@test1 bin]$ /home/tomcat/instance1/apache-tomcat-8.5.9/bin/startup.sh
Using CATALINA_BASE:   /home/tomcat/instance1/apache-tomcat-8.5.9
Using CATALINA_HOME:   /home/tomcat/instance1/apache-tomcat-8.5.9
Using CATALINA_TMPDIR: /home/tomcat/instance1/apache-tomcat-8.5.9/temp
Using JRE_HOME:        /home/tomcat/java/jdk1.8.0_112
Using CLASSPATH:       /home/tomcat/instance1/apache-tomcat-8.5.9/bin/bootstrap.jar:/home/tomcat/instance1/apache-tomcat-8.5.9/bin/tomcat-juli.jar
Tomcat started.
[tomcat@test1 bin]$

[tomcat@test1 bin]$ /home/tomcat/instance2/apache-tomcat-8.5.9/bin/startup.sh
Using CATALINA_BASE:   /home/tomcat/instance2/apache-tomcat-8.5.9
Using CATALINA_HOME:   /home/tomcat/instance2/apache-tomcat-8.5.9
Using CATALINA_TMPDIR: /home/tomcat/instance2/apache-tomcat-8.5.9/temp
Using JRE_HOME:        /home/tomcat/java/jdk1.8.0_112
Using CLASSPATH:       /home/tomcat/instance2/apache-tomcat-8.5.9/bin/bootstrap.jar:/home/tomcat/instance2/apache-tomcat-8.5.9/bin/tomcat-juli.jar
Tomcat started.
[tomcat@test1 bin]$

On WebServer Machine

==================

[root@test2 logs]# service httpd start
Redirecting to /bin/systemctl start  httpd.service
[root@test2 logs]#

12) Test the set up using below WebServer URL

http://192.168.52.161/examples/