Tuning LAMP Server Performance

Having trouble with a crashing webserver? Is MySQL or Apache eating up your RAM and trashing your drive swapping? Don’t worry, there are good tools to help you get started in tuning your LAMP server to avoid crashes.

There are two scripts that I find invaluable in getting me a first and fast opinion on the current status of the server. The trick is often to get the settings right so that they do not risk eating up your RAM for breakfast. Here are two scripts to help you get your MySQL and Apache settings right for you.

This script will test your MySQL settings and suggest performance improvements. By using statistics from MySQL of current state of performance it will suggest modifications to your settings.

Inspired by MySQLtuner.pl Apachebuddy.pl does the same thing to Apache server settings. It checks your current settings and calculates average as well as maximum RAM usage and suggest improvements.

These script does of course not replace knowledge. Use them as a first opinion but then educate yourself about the settings before changing anything.

Both scripts have nifty URLs to download from:

Free software is amazing

Almost all software I use is or is built upon free software. I believe Microsoft Office is one of the few major exceptions to this (in my program library).

This makes me think of Tron…
“I fight for the user!”

Attack on WordPress – is WordPress secure?

wordpressSecurity firms are reporting a very large attack on what seems to be all sites using WordPress. One WordPress host reported an increase of an average of 40k failed logins per month to 77k failed logins per day! The failed logins are coming from a large amount of different IP-numbers and is therefore hard to block. The advice from Matt Mulleweg, creator of WordPress, is: remove the old standard admin-account (if it still exists), use a strong password and as always, keep your WordPress installation up to date!

This brings up the question “is WordPress a secure platform?”. In my opinion the answer is a resounding YES! If the hackers have a bot network at their disposal and the means of attack is a brute force password attack then there really isn’t much you can do about it. Had WordPress had any known single fatle flaw the hackers would have used that instead. Apparently it doesn’t!

Any platform large enough will be the target of hackers, much like Windows is under heavy attack as a operating system. There have been known bugs in WordPress, allthough the latest such vulnerability was acctually a bug in a popular templates subclass and not in WordPress in itself. The WordPress community quickly responded and fixed the bug.

I feel secure to continue to use WordPress as my main platform for my blogs, so should you!

Creating a MySQL Master – Slave connection

I’ve setup several MySQL Master – Slave connections and like to share my procedure. During the trials there are several details I’ve come to learn how to handle and my own set of “best practices”.

The MySQL Master Slave connection works under the premise that “a statement executed on the master should create the exactly same result when executed on the slave given that their database is equal”. For this to work we need to start two servers that are identical and then make one follow the other.

We used MySQL Server 5.5.11 when creating the master slave connection in the guide below. Please consult the MySQL Documentation if you are using a different version.

Step 1: Setup servers
First of all you will need two MySQL-servers. The standard community edition works fine. They should be of the exact same version to avoid any problem that bugs in one or the other might introduce. If you introduce a slave into an existing MySQL server you will need to make plan for a downtime for the duration of running the “mysqldump” command.

TIP: Save the MySQL installation file if you want to add more servers later since you will need the exact same version.

Step 2: Configuration
Edit the my.ini-file off the future master and add the following settings:

# Unique Server ID
# Name of binary log

The Server ID can be any number as long as there are no two servers with the same number in the replication chain, i.e. in our case the slave must have a different number.

The log-bin setting tells the server to make a binary log of every statement executed on the server.

Edit the my.ini file off the future slave and add the following settings:

# Unique Server ID

TIP: Add the setting relay-log=relay-bin to name the relay log. Otherwise MySQL by default uses [hostname]-relay-bin. The problem with the default is that if the host ever change hostname the replication will break. It also breaks if you want to make a copy of the slave to a second slave (if you do not add the setting to the new slave as well).

As mentioned before, the Server ID of the slave needs to be different from the Server ID of the master. When these changes are done, restart the service on both MySQL machines to let the changes take effect. Use the following commands to restart the service:

Linux (requires super user access):

user@host:~$ service mysql restart

Windows (requires administrator privileges):

C:\net stop mysql
C:\net start mysql

After the changes you should see a binary log starting to grow in data data directory of your future master.

TIP: If you have made other modifications to the my.ini file these needs to be copied as well to the slave, otherwise the slave riscs behaving differently from the master.

Step 3: Create a user
The replication will be using a normal user with the replication privilege. I opted to create a new user for this using the following commands:

mysql> CREATE USER 'slave'@'%' IDENTIFIED BY 'mytrickypassword';
mysql> GRANT REPLICATION SLAVE ON *.* TO 'slav'@'%';

The user will be created on the master but if you replicate all databases (as this guide will) then the user will also be replicated to the slave.

TIP: You can use any password you like BUT the password will be visible in plain text on the slave server! In the file master.info that will be created later in this tutorial all the master information will be stored including username and password.

TIP: Make the slave user limited to a certain domain or IP so that security riscs will be minimized. In the above example the user slave can log in from any host.

Step 4: Copy database
Now the time critical portion of this tutorial begins, from here until the datadump is complete the master database will be unavailable for writing.

Execute the following command on the MySQL Master:


Now all tables will be locked so that no transactions can occur. This is required since we need to make a full database dump of the current state of MySQL Master. Next execute the following command:


Write down the reply of the following values: File and Position. An example would be:

File: mysql-bin.00001
Position: 1337

From the command line on the MySQL master issue the following command (change password etc as needed):

C:\mysqldump --user=root --password=rootpassword --all-databases --master-data --result-file=mydump.sql

TIP: Are you using non UTF-8 encoding? Add “–default-character-set=latin1” to the command line where latin1 is the encoding you are using. If you do not supply an encoding MySQL will assume UTF-8.

When the dump is complete and you have a file called mydump.sql you can unlock the tables. Issue the unlock command on the master:


The master server will now be on-line and working again.

Step 5: Create the slave
Copy the file mydump.sql to the slave server. When it is done execute the following command from the mysql command line (you might have to specify exact location of the mydump.sql file):

mysql> source mydump.sql

TIP: Do NOT use “mysql -u root -p < mydump.sql” from the normal command line since that can corrupt the encoding, again if you use non-standard encoding.

The database on the slave is now identical to what the master from a specific point in time. Now configure the slave to connect to the master and follow it from that point in time.


Make sure that MASTER_HOST is the name or IP of the MySQL Master. MASTER_USER and MASTER_PASSWORD are the same as created in step 3 above. MASTER_LOG_FILE and MASTER_LOG_POS are the same as read from step 4 above.

TIP: Since we used the flag –master-data when creating mydump.sql the MASTER_LOG_FILE and MASTER_LOG_POS should allready be set. The remaining settings are however needed.

TIP: Unless you specifically need it I recommend to avoid using binary logging on the slave while it tries to “catch up” with the master. Also the “bin-log” command only triggers logging of commands executed directly on the server, not from replication. To make the slave write replication to it’s own binary log the following setting must be added: “log-slave-updates=1”.

Start the slave with the following command from MySQL command line:


Step 6: DONE
Congratulations, your slave server is now replicating everything on the master server. Depending on how long time it took between step 4 and step 5 the slave should most likely allready have caught up the the master. To check on the status run the following command on the slave server:


Especially noteworthy fields in this reply are “Slave_IO_State” that informs us of what the slave is up to, most common reply here is “Waiting for master to send event”. “Seconds_Behind_Master” tells us how many seconds behind the slave server is at the moment. If the slave server has been done or restored to an old backup this value can be very high. Normally this value is zero indicating that the slave is up to speed.

TIP: Did you know you can “daisy chain” MySQL servers. Just setup the slave as master to a new slave! There are however some further considerations for doing that, maybe a future blog post!

TIP: The slave server is perfect to use as a “live backup” in case the master should fail. You can also temporarily stop/lock the slave to make a complete database backup without having to worry about downtime of the service. The slave will catch up with the master again once started.

TIP: As with every security meassure in information technology, try this out before trusting how it works! I give NO GUARANTEE OF ANYTHING WRITTEN IN THIS GUIDE, you have to try and verify it yourself. This works for me, it doesn’t necessarily work for you.

More tips, comments or questions? Please feel free to comment below!

Piwik fyller 1.0

Så har Piwik nått den ansenliga “åldern” av 1.0! Statistikverktyget har länge fungerat väldigt bra men nu i och med att den får version 1.0 vill utvecklarna säga att det nu mognat och kan uppfylla följande krav:

  • ett kompetent webb-analys-program
  • mycket bra användarupplevelse
  • kraftfullt gränssnitt för att skriva tillägg
  • en aktiv grupp utvecklare

Själv använder jag Piwik för flera av mina hemsidor och i stora delar har det nu även i min mening blivit bättre än Google Analytics. Framförallt är det möjligheten att individuellt anpassa programmet som är mycket mer flexibelt i Piwik.

osCommerce – tableCommerce

Aldrig förr har jag skådat så många tabeller som när jag arbetar med osCommerce. De som skrev basen till osCommerce måste verkligen ha älskat table-taggen. Förvisso var tables nästan oumbärlig för ett antal år sedan när det kom till layout inom HTML, men inte ens om man ser hur tabeller då borde ha använts är osCommerce-koden nämnvärt vacker. Där är nestade tabeller i så många nivåer att det är snudd på omöjligt att upptäcka var den ena börjar och den andra slutar.

WordPress 3.0.1 ute

Så kör jag bloggen på nya WordPress 3.0.1! Den nya version tre känns vid första anblick inte speciellt annorlunda från tidigare versioner, dock känns det dagligen som man hittar någon ny liten finess.

En av de mer välkomna nyheterna är den anpassningsbara menyn. Detta öppnar för nya möjligheter att utveckla mallar med special-menyer för olika ändamål.

WordPress as a simple CRM

I recently started a new business where I really want to focus on taking care of the customer needs, being proactive rather than reactive to them. As such I need a simple Customer Relations Management (CRM) tool to keep track of my promises and contacts. There are probably many simple CRM tools available but I decided to try out WordPress as a CRM tool.

First I installed WordPress on an internal server with no external connection. I set the firewall to block that server from traffic with the outside network and then I started to do my internal “company blog”. To structure things I decided to follow some simple rules:

  • I make one post for every type of contact (e-mail / phone / order etc) I do every day, if several contacts to the same company / person occurs the same day they still only get one.
  • Several types of contact to the same company / person will get multiple posts the same day
  • Categories are other authorities, companies and/or persons
  • Tags are techniques, events, frameworks etc.

On average I get three to four posts every day, usually covering a broad area. Some days there are big events which often are reflected in the blog/CRM by only having one post for that day. Amounts of posts per day is therefore irrelevant. I keep the posts very short, they are mainly thought of as references to other information like an e-mail or something else. If it was a phone conversation I usually take down a few simple sentances of what the discussion was about.

Three months later I now use this internal blog alot! It helps me keep track of events that I might have forgotten about. When I had a tax issue recently I could quickly click the “tax authority” category and see which days I had communicated with them and leave as a reference in my future communication.

One thing that also helps me is the simplicity of clicking a category to bring up all the communication with that customer. When someone calls I quickly click their category and all my previous conversations with them are recorded. It helps me quickly remember what we where talking about, just like a CRM should.

There are of course limitations, WordPress was never intended to be used this way. There are no way to search for inactive customers for example, should the need for this arise a plugin for WordPress could most certainly easily be developed. Furthermore you need to be very careful about where you install the software so you do not publish all your information on the Internet. I run my business alone but this setup would work very nice also with a few employees I would imagine. Everyone could be an author in the same blog and you can access what the other persons are working on should a customer call when they are out.

The simplicity of WordPress makes this a great choice for me!