Category Archives: Uncategorized

>Add disclaimer in Exim

Tweet> As a Mail Admin , you may get task to add disclaimer to the outgoing mails of your mail server . Let me remind you that adding disclaimer may have some legal aspects and many people suggest not to add any disclaimer by altering mail content on the mail server. If you still want… Read More »

>Sendmail Spamming Prevention

Tweet> Sendmail is defame for security holes. But this is also a fact that sendmail is one of popular MTA. Its not possible to avoid spamming through sendmail completely but yes sendmail can be configured in better way to limit spamming though it.  I am here discussing some of the options which can be useful… Read More »

>What is LUN?

Tweet> If suppose we got a large storage array, and requirement is to not allow one server to use all storage spaces, so it need to divided into logical units as LUN(Logical Unit Number). So LUN allow us slice storage  array into usable storage chunks and present same to server. LUN basically refer to either… Read More »

>Bandwidth testing using command

Tweet> Sometime we need to test bandwidth between two linux system. Here in this post i am showing by example to test bandwidth without any network monitoring tool.Suppose you need to test bandwidth between two linux hosts one in Host1 and another is Host2. Execute following command on Host1    root@Host1# nc -u -l 7654 >/dev/nullOn… Read More »

>chroot ftp user

Tweet> I am using vsftpd as ftp server on RHEL 5. I published a folder using vsftpd and try to access that folder using ftp client FileZilla. The problem is that filezilla shows physical path of ftp folder. This can be a security concern . To solve this problem, i made following entry in vsftpd… Read More »

>nginx configuration

Tweet> To enhance the performance and security of my web server , few days back i decided to use Reverse proxy theory. My idea was to put a a lightweight web server in front of my apache web sever to serve all the static contents by that lightweight web server, and dynamic content by main… Read More »

>Whats New In RHEL 6

Tweet> RHEL 6 released last week. There are may new features has been added and some works on performance enhancement has been done as will virtualization get some maturity. Follow this link to get broad idea on new features in RHEL6. I will be here with more updates and trying it. There is some… Read More »


Tweet> This is holiday weekend in india. The festival of light DIWALI is tommorow. I wish HAPPY DIWALI to all of you. Great celebration with lights and crackers is awaiting. I am very much excited and want to request that ‘TRY TO AVOID TOO MUCH CRACKERS‘, Believe me same sort of enjoyment and cheers can… Read More »

>Country security is most important.

Tweet>CWG games are going to be held in my country(india) in this month . Although our top govt official embarras us a lot by their acts, but its our responsibilty to prove that we are aware citizens. Now a days lots of news coming about misuse of insecure wireless internet connections by terrorists organizations. In… Read More »

>Linux kernel security

Tweet>Where security is top priority , we first focus on security of Linux kernel. Although by default linux kernel are not very secure , there are important linux kernel patches to secure your linux box. These kernel patches are SELinux , AppArmor and Grsecurity. These patches control access between processes to objects, processes to processes… Read More »