How to Change default MySQL Data Directory in Linux

As a System Administrator I don’t prefer to use / directory to store MySQL data files. Each time when I install MySQL for a production server, I tried to use secondary disk for storing application and database file. In that way I always change the default data directory of MySQL to secondary disk mounted on system. Mostly MySQL uses /var/lib/mysql directory...

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IP ROTATION VIA IP TABLES

First we need creating Interface aliases for your public IPs. Let's say you have 5 ips #ifup eth0:1 #ifup eth0:2 #ifup eth0:3 #ifup eth0:4 Now the iptables part.make sure your iptables support for statistic match module. # iptables -m statistic -h ...... ...... ...... statistic match options: --mode mode Match mode (random, nth) random mode: --probability p ...

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Solved: Error compiling httpd-2.2.23: byterange_filter.c:(.text+0x12c1): undefined reference to `apr_array_clear’

modules/http/.libs/libmod_http.a(byterange_filter.o): In function `ap_set_byterange': byterange_filter.c:(.text+0x12c1): undefined reference to `apr_array_clear’ collect2: ld returned 1 exit status Solution: Add this to the configure command: --with-included-apr with compliments and kind regards to Stefan for providing this soluti...

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How to check if your Linux server is under DDOS Attack?

Login to your server as root and fire the following command, using  which you can check if your server is under DDOS attack or not: netstat -anp |grep ‘tcp\|udp’ | awk ‘{print $5}’ | cut -d: -f1 | sort | uniq -c | sort –n This command will show you the list of IP’s which have logged in is maximum number of connections to your server. ddos becomes more complex as attackers ...

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How To Implement SPF In Postfix

This tutorial shows how to implement SPF (Sender Policy Framework) in a Postfix 2.x installation. The Sender Policy Framework is an open standard specifying a technical method to prevent sender address forgery (see http://www.openspf.org/Introduction). There are lots of SPF extensions and patches available for Postfix, but most require that you recompile Postfix. Therefore we will install the...

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Configuring Reverse DNS in BIND 9

Reverse DNS is the process of using DNS to translate IP addresses to hostnames. Reverse DNS is the opposite of Forward DNS, which is used to translate hostnames to IP addresses. One way to see reverse DNS at work is to use nslookup a tool on most OS’s. Let’s use `nslookup` to do a forward and reverse DNS lookup on redhat.com: ##FORWARD LOOKUP [phil@ns1 ~]$ nslookup redhat.com Server: ...

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