Posts Tagged ‘configuration issue’

Tracking graphically MySQL, Apache and Network performance in web with Munin on Debian Linux

Saturday, March 19th, 2011

munin_monitor_cpu_network_hard_drive_apache_mysql_performance-in-web-on-linux_logo

Munin is great software for surveillance software for your MySQL, Apache, Qmail, Postfix and many other of the classical daemon services which most of the Linux, BSD servers online are running on.

1. Munin on Debian Linux is really easy to be installed and comes to executing:

debian:~# apt-get install munin munin-node munin-plugins-extra

2. Link /var/www/munin/ to some VirtualHost or ServerHost
For instance if your munin is to be placed on the domain pc-freak.net.net which has the DocumentRoot of /var/www

debian:~# cd /var/www
debian:/var/www# ln -sf /var/www/munin munin

3. Add some extra MySQL related plugins

To check whole list of pmunin plugins you can enable check in /etc/munin/plugins directory

Lets say our Munin will be providing statistics mainly for MySQL, enable this bunch of plugins:

cd /etc/munin/plugins
ln -s /usr/share/munin/plugins/mysql_ mysql_
ln -s /usr/share/munin/plugins/mysql_bytes mysql_bytes
ln -s /usr/share/munin/plugins/mysql_innodb mysql_innodb
ln -s /usr/share/munin/plugins/mysql_isam_space_ mysql_isam_space_
ln -s /usr/share/munin/plugins/mysql_queries mysql_queries
ln -s /usr/share/munin/plugins/mysql_slowqueries mysql_slowqueries
ln -s /usr/share/munin/plugins/mysql_threads mysql_threads


Though above command would enable mysql monitoring it will be not working out of the box. You will find in munin logs error like:

Missing dependency Cache::Cache at /usr/share/munin/plugins/mysql_ line 716."

To fix this install libcache-perl and libcache-cache-perl

apt-get install --yes libcache-perl libcache-cache-perl
 

Then regenerate munin plugin configuration issue cmd:

munin-node-configure --suggest --shell | sh

and restart Munin-node server

service munin-node restart
 

Munin Node should be able login to the MySQL server using the Debian System Maintenance user however if you should need to create a custom user you can add the following configuration to:
 

/etc/munin/plugin-conf.d/munin-node

 

[mysql*]
    user root
    env.mysqluser muninmonitor
    env.mysqlpassword Your-Secret-Password

4. Edit Munin config

Make sure you have at least the following variables enabled in /etc/munin/munin.conf
 

 dbdir  /var/lib/munin
 htmldir /var/cache/munin/www
 logdir /var/log/munin
 rundir  /var/run/munin

 tmpldir    /etc/munin/templates

includedir /etc/munin/munin-conf.d

[localhost.localdomain]
    address 127.0.0.1
    use_node_name yes

 

5. Add Munin Alias or Virtualhost

To make Munin Accessible from Webserver you need to at least add an alias create a file
/etc/apache2/conf.d/munin with following content:

vim /etc/apache2/conf.d/munin

Alias /munin /var/cache/munin/www

<Directory /var/cache/munin/www>
        Order allow,deny
        #Allow from localhost 127.0.0.0/8 ::1
        Allow from all
        Options None
        php_value engine off

    <IfModule mod_expires.c>
        ExpiresActive On
        ExpiresDefault M310
    </IfModule>

</Directory>


If you want to access Munin from Apache subdomain create it lets say you want to access it via stats.pc-freak.net, use following config file:

vi /etc/apache2/sites-enabled/stats.pc-freak.net
 

<VirtualHost *>
   ServerAdmin hipo@pc-freak.net
   ServerName stats.pc-freak.net
   DocumentRoot /var/cache/munin/www
   <Directory />
       Options FollowSymLinks
       #AllowOverride All
       php_value engine off
   </Directory>
   LogLevel debug
   CustomLog /var/log/apache2/munin/access.log combined
   ErrorLog /var/log/apache2/munin/error.log
   ServerSignature On
<Directory /var/cache/munin/www>
        Order allow,deny
        #Allow from localhost 127.0.0.0/8 ::1
        Allow from all
        Options FollowSymlinks
        #AllowOverride All
        php_value engine off

</Directory>

</VirtualHost>

 


6. Restart Apache;

debian:~# /etc/init.d/apache2 restart

Now to access the newly installed munin point your favorite browser to (either the subdirectory configured for access or the Virtualhost subdomain):

http://www.pc-freak.net/munin/
or
http://munin.pc-freak.net

eth0-network-traffic-munin-server-statistics

connections_through_firewall-statistics-munin-debian-linux
7. Protecting Munin with a password

As it could be a security leak to expose statistics regarding your server (Disk I/O, Memory, Load Avarage, Apache, MySQL Postfix) operations it is good security practice to protect munin with a password.

I've earlied blogged on how to protect your server munin web-statistics wtih an htaccess password (read it here)


munin-cup-statistics-by-day-and-by-month-screenshot

Happy Monitoring

Installing the phpbb forum on Debian (Squeeze/Sid) Linux

Saturday, September 11th, 2010

howto-easily-install-phpbb-on-debian-gnu-linux

I've just installed the phpbb forum on a Debian Linux because we needed a goodquick to install communication media in order to improve our internal communication in a student project in Strategic HR we're developing right now in Arnhem Business School.

Here are the exact steps I followed to have a properly it properly instlled:

1. Install the phpbb3 debian package
This was pretty straight forward:

debian:~# apt-get install phpbb3

At this point of installation I've faced a dpkg-reconfigure phpbb deb package configuration issue:
I was prompted to pass in the credentials for my MySQL password right after I've selected the MySQL as my preferred database back engine.
I've feeded my MySQL root password as well as my preferred forum database name, however the database installation failed because, somehow the configuration procedure tried to connect to my MySQL database with the htcheck user.
I guess this has to be a bug in the package itself or something from my previous installation misconfigured the way the debian database backend configuration was operating.
My assumption is that my previously installed htcheck package or something beforehand I've done right after the htcheck and htcheck-php packages installation.

after the package configuration failed still the package had a status of properly installed when I reviewed it with dpkg
I've thought about trying to manually reconfigure it using the dpkg-reconfigure debian command and I gave it a try like that:

debian:~# dpkg-reconfigure phpbb3

This time along with the other fields I've to fill in the ncurses interface I was prompted for a username before the password prompted appeared.
Logically I tried to fill in the root as it's my global privileges MySQL allowed user.
However that didn't helped at all and again the configuration tried to send the credentials with user htcheck to my MySQL database server.
To deal with the situation I had to approach it in the good old manual way.

2. Manually prepare / create the required phpbb forum database

To completet that connected to the MySQL server with the mysql client and created the proper database like so:

debian:~# mysql -u root -p
mysql>
CREATE database phpbb3forum;

3. Use phpmyadmin or the mysql client command line to create a new user for the phpbb forum

Here since adding up the user using the phpmyadmin was a way easier to do I decided to go that route, anyways using the mysql cli is also an option.

From phpmyadmin It's pretty easy to add a new user and grant privileges to a certain database, to do so navigate to the following database:

Privileges -> -> Add a new user ->

Now type your User name: , Host , Password , Re-type password , also for a Host: you have to choose Local from the drop down menu.

Leave the Database for user field empty as we have already previously created our desired database in step 2 of this article

Now press the "Go" button and the user will get created.

Further after choose the Privileges menu right on the bottom of the page once again, select through the checkbox the username you have just created let's say the previously created user is phpbb3

Go to Action (There is a picture with a man and a pencil on the right side of this button

Scroll down to the page part saying Database-specific privileges and in the field Add privileges on the following database: fill in your previosly created database name in our case it's phpbb3forum

and then press the "Go" button once again.
A page will appear where you will have to select the exact privileges you would like to grant on the specific selected database.
For some simplicity just check all the checkbox to grant as many privilegs to your database as you could.
Then again you will have to press the "Go" button and there you go you should have already configured an username and database ready to go with your new phpbb forum.

4. Create a virtualhost if you would like to have the forum as a subdomain or into a separate domain

If you decide to have the forum on a separate sub-domain or domain as I did you will have to add some kind of Virtualhost into either your Apache configuration /etc/apache2/apache2.conf or into where officially the virutualhosts are laid in Debian Linux in /etc/apache2/sites-available
I've personally created a new file like for instance /etc/apache2/sites-available/mysubdomain.mydomain.com

Here is an example content of the new Virtualhost:

<VirtualHost *>
ServerAdmin admin-email@domain.com
ServerName mysubdomain.domain.com

# Indexes + Directory Root.
DirectoryIndex index.php index.php5 index.htm index.html index.pl index.cgi index.phtml index.jsp index.py index.asp

DocumentRoot /usr/share/phpbb3/www/

# Logfiles
ErrorLog /var/log/apache2/yourdomain/error.log
CustomLog /var/log/apache2/yourdomain/access.log combined
# CustomLog /dev/null combined
<Directory /usr/share/phpbb3/www/>
Options FollowSymLinks MultiViews -Includes ExecCGI
AllowOverride All
Order allow,deny
allow from all </Directory>
</VirtualHost>

In above Virtualhost just change the values for ServerAdmin , ServerName , DocumentRoot , ErrorLog , CustomLog and Directory declaration to adjust it to your situation.

5. Restart the Apache webserver for the new Virtualhost to take affect

debian:~# /etc/init.d/apache2 restart

Now accessing your http://mysubdomain.domain.com should display the installed phpbb3 forum
The default username and password for your forum you can use straight are:

username: admin
password: admin

So far so good you by now have the PHPBB3 forum properly installed and running, however if you try to Register a new user in the forum you will notice that it's impossible because of a terrible ugly message reading:

Sorry but this board is currently unavailable.

I've spend few minutes online to scrape through the forums before I can understand what I have to stop that annoying message from appearing and allow new users to register in the phpbb forum

The solution came natural and was a setting that had to be changed with the forum admin account, thus login as admin and look at the bottom of the page, below the text reading Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group you will notice a link with Administration Control Panel
just press there a whole bunch of menus will appear on the screen allowing you to do numerous things, however what you will have to do is go to
Board Settings -> Disable Board

and change the radio button there to say No

That's all now your forum will be ready to go and your users can freely register and if the server where the forum is installed has an already running mail server, they will receive an emails with a registration data concerning their new registrations in your new phpbb forum.
Cheers and Enjoy your new shiny phpbb Forum 🙂