Faced today a problem on one CentOS 5.4 server. After update server was dropping connections, sometimes pings were lost.

Many months passed since my last posting. I guess I will no longer use this blog for long postings. I will try to bring back to life posting small tips and tricks just not to forget myself.

First one will be booting xen virtual guest into the single mode. (Read more...)

Today CentOS announced 5.3 release. Now we know the delay between RHEL and CentOS releases. RHEL GA 5.3 was released on 20.01.2009. It took more then 2 months for CenOS team to clone new system.

If this is isn't April's fools news :)

There was a request for me to install ipf filter package on one Solaris 9 x86 box. Unfortunately there is no precompiled package on http://www.sunfreeware.com/. http://coombs.anu.edu.au/~avalon/ipf-mentat.html says - Install pfil and then to just "make solaris" in the ipf directory, followed by a "cd SunOS5; make install". But it would be too easy. (Read more...)

"Why pay for RedHat RHEL if there's CentOS?" somebody may think.

One of the answers is here. Just check it out - most of the vulnerabilities RedHat fixed during one day. For example, "Non-Browser" applications (e.g. Samba, Sendmail, OpenSSH, Gaim, evolution) had 16 issues, with average fixing time 14 hours, and 94% of issues were fixed during one day. (Read more...)

In the previous part we have realized that we have disk actually smaller, then we thought, when we were buying it. Now we will investigate what is the overhead of the ext3 file system itself, where and why the space is used. (Read more...)

In the following 3 articles (Part 2, Part 3) I will show where is free space of your freshly installed disk gone, what is the overhead of the ext3 file system, how exactly this overhead is used and how we can reduce it to maximise effective usage of the ext3 filesystem. (Read more...)

On my i386 test server upgrade from CentOS 4.5 to CentOS 5.2 took approximately 60 minutes with all downloads, etc... And the only commands I issued are (taken from http://wiki.centos.org/HowTos/MigrationGuide/ServerCD_4.4_to_5 ) (Read more...)

This little howto will help you boot some linux kernel from your grub configuration only once. During the next boot grub will boot as usual. (Read more...)