Apache and syslog-ng

While logging to a database back-end has its benefits, the setup as it stands leaves us wanting. Some applications, such as Apache, do not log via syslog-ng by default. The good news is that this can be easily remedied, and there are a couple of different ways of doing this. First, the less good way:

Method #1: Changing the Apache configuration file.

First, we need to setup syslog-ng appropriately by creating a new source for apache, such as the following:

source s_apache {
 unix-stream("/var/log/apache2/apache_log.socket"
 max-connections(512)
 keep-alive(yes));
 };

log { source(s_apache); destination(d_pgsql); };

This recycles the original destination for …

Last week I wrote about my experience compiling Drizzle 7 on Mac OS X 10.6. Then David Shrewsbury informed me of his nearly identical blog post: Installing Drizzle from source on OS X. Once Drizzle 7 was running on my box, I immediately looked to see what plugins where available because Drizzle uses a lot of plugins and they are one of its notable differences from MySQL. In my humble opinion, Drizzle’s plugins will primarily influence how database professionals evaluate and decide whether or not to use Drizzle because so many of Drizzle’s features are plugins. Therefore, let’s look briefly at some the plugins included with Drizzle 7.

The plugin directory of the Drizzle 7 tarball lists 79 plugins. Each plugin …

<p>The easiest way to get user statistics from your own site is probably binding third-party tools like, e.g. Google Analytics into your code or parsing the logfiles with AWstats or webalizer. Evaluating your own logged data is the best way to look over the (imaginary) shoulder of users and bots. Moving static content on different servers remain the accesslog also manageable and free from unnecessary data.</p>

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System administrators familiar with the Linux operating system use the tools in the 'procps' toolset all the time. Tools which read from /proc include top, iostat, vmstat, sar and others. The files in /proc contain useful information about the performance of the system. Most of the files are documented in the Linux kernel documentation. You can also check man 5 proc.

Most performance monitoring tools invoke other tools like iostat to collect performance information instead of reading from the /proc filesytem itself. This begs the question, what can you do if you don't have access to those tools? Perhaps you are using a hosted Linux database and have no access to the underlying shell to execute tools like iostat or top? How could you gather information about the performance of the actual system without being allowed to run the tools?
…

In my previous post, Capturing Erroneous Queries with MySQL Proxy, I showed how to capture erroneous queries, along with relevant information, that one could not effectively obtain from the MySQL general query log. However, in that post, I simply output the information to the terminal. Therefore, in this example, I want to show how to write this information to a proxy log file.

To change this to log to a log file does not require too many changes, and so this is a useful example on how to log any proxy-related information to a log file.

1. I perform a check for an existing log file (at least using the variable of name “log_file”), and then assign log_file to the location of where I want the log file to reside (at the beginning of the lua script).

   if (log_file == nil) then
     log_file = "C:/Program Files/MySQL/mysql-proxy-0.7.2/proxy.log"
   end

…

Long before there was the official Query Analyzer (QUAN), a component of MySQL Enterprise, SQL analysis was possible using MySQL Proxy.

The following is an introduction to logging and query analysis with MySQL Proxy.

Get MySQL Proxy

You need to first download MySQL Proxy. In this example I am using the Linux RHEL5 64bit OS and Version 0.7.2

$ wget http://dev.mysql.com/get/Downloads/MySQL-Proxy/mysql-proxy-0.7.2-linux-rhel5-x86-64bit.tar.gz/from/http://mirror.trouble-free.net/mysql_mirror/
$ tar xvfz mysql-proxy-0.7.2-linux-rhel5-x86-64bit.tar.gz
$ ln -s mysql-proxy-0.7.2-linux-rhel5-x86-64bit mysql-proxy
$ export PATH=`pwd`/mysql-proxy/sbin:$PATH
$ mysql-proxy --help-all

Pre-requisites

MySQL Proxy uses TCP/IP, so it is important you connect via the actual …

I came across a situation recently where I was asked if it was possible to edit a binary log to remove a part of it to restore onto a slave server. Now the choice of doing something like a hexedit did not seem appealing, and the more experienced might suggest that it is simply a matter of using  mysqlbinlog with the --start-position and/or --stop-position options. However, the problem had arisen that required the binary log to played through the replication process onto the slave based on specific options in MySQL cluster, so using an SQL dump from the binary log was of no use.

Initially this may seem like a daunting task where you will have to find some specialist tool or delve into the deep recesses of the binary log format, but a much simpler solution was found. The replication process allows the slave to be started up to a specific point in the log files. The command is the START SLAVE UNTIL... statement as seen in the manual at: …

I came across a situation recently where I was asked if it was possible to edit a binary log to remove a part of it to restore onto a slave server. Now the choice of doing something like a hexedit did not seem appealing, and the more experienced might suggest that it is simply a matter of using  mysqlbinlog with the --start-position and/or --stop-position options. However, the problem had arisen that required the binary log to played through the replication process onto the slave based on specific options in MySQL cluster, so using an SQL dump from the binary log was of no use.

Initially this may seem like a daunting task where you will have to find some specialist tool or delve into the deep recesses of the binary log format, but a much simpler solution was found. The replication process allows the slave to be started up to a specific point in the log files. The command is the START SLAVE UNTIL... statement as seen in the manual at: …

I came across a situation recently where I was asked if it was possible to edit a binary log to remove a part of it to restore onto a slave server. Now the choice of doing something like a hexedit did not seem appealing, and the more experienced might suggest that it is simply a matter of using  mysqlbinlog with the --start-position and/or --stop-position options. However, the problem had arisen that required the binary log to played through the replication process onto the slave based on specific options in MySQL cluster, so using an SQL dump from the binary log was of no use.

Initially this may seem like a daunting task where you will have to find some specialist tool or delve into the deep recesses of the binary log format, but a much simpler solution was found. The replication process allows the slave to be started up to a specific point in the log files. The command is the START SLAVE UNTIL... statement as seen in the manual at: …

In two words: online operations. In a paragraph: Forget partitioning, row-based replication and events. The big reasons most people are going to salivate over 5.1, and probably start plans to upgrade now, are the online operations:

• online ALTER TABLE for column rename, column default value change, and adding values to the end of an ENUM/SET
• Online, table-based logging. No more need to restart your server to enable or change the general or slow query logs. You can have the standard file-based output or choose a table format…which you can query.

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