Nginx: embedding Lua into webserver

Lua is a tiny but powerful programming language. Due to its small memory footprint (about hundreds of kilobytes) it’s widely used in application which need to be extended with more complex logic. For instance, Salvatore Sanfilippo has published a  post describing how you can use power of Lua with Redis. It also applied to nginx,…
Read more

Using RRD with Python: short introduction

RRDtool is a great facility which aims to replace MRTG and was written by Tobias Oetiker. RRDtool provides powerful features for collecting and visualizing various system metrics like network traffic, MySQL counters or whatever you want. It’s always good idea to know what is going on under the hood of your server. Managing servers we…
Read more

Fixing ‘Missing dependency Cache::Cache at /usr/share/munin/plugins/mysql_’ error

While installing MySQL plugins for munin in Fedora 15 you may encounter this problem: [root@monitor plugins]# /usr/share/munin/plugins/mysql_ suggest Missing dependency Cache::Cache at /usr/share/munin/plugins/mysql_ line 716. [root@monitor plugins]# It means that your system lacks perl-Cache-Cache and perl-IPC-ShareLite packages. After installation you can proceed: yum install perl-Cache-Cache perl-IPC-ShareLite [root@monitor plugins]# /usr/share/munin/plugins/mysql_ suggest bin_relay_log commands connections files_tables innodb_bpool…
Read more

Cleaning ‘Failed actions’ message in Pacemaker/Corosync cluster setup

Sometimes when using Pacemaker/Corosync-based cluster you can see warning message in crm_mon output: Failed actions: drbd_mysql:0_promote_0 (, call=11, rc=-2, status=Timed Out): unknown exec error  To clean it up you can use command crm_resource which checks health of resources: [root@node1 ~]# crm_resource -P Waiting for 1 replies from the CRMd. OK [root@node1 ~]# To check…
Read more

Automatic GeoIP database update

Free binary GeoLite Countrydatabase by MaxMind is being  updated every month. To update it automatically you can  put this script to cron at the beginning of a month. That’s it. Didn’t find the answer to your question? Ask it our administrators to reply we will publish on website.

RPM: building proctitle for PHP

Sometimes it’s convenient to change PHP script name, it allows to check if it’s running by typing just pstree. You can perform that with use of proctitle. Unfortunately there is no rpm for this package for Fedora 15. So to use it you need to build it. Firstly you need to download source package to…
Read more

RPM: how to build Redis library package for PHP

At Supportex we use Redis a lot. It’s extremely fast and doesn’t consume a lot of resources.  Besides it’s easy to use for developers (especially for those who worked with Memcache). Unlike Python which has only one mature client, PHP has various of them.  For instance, Predis, phpredis,  Rediska, etc. We prefer phpredis. It’s written…
Read more