CentOS Linux 7.7 released and here is how to update it

last updated in Categories Howto, Linux News, Open Source

The CentOS Linux project has released an updated version of its stable Linux distribution CentOS Linux 7.7. You must upgrade to get corrections for security problem as this version made a few adjustments for the severe issue found in CentOS 7.6. CentOS is a Linux distro that is mainly maintained and updated through the work of many users who volunteer their time and effort. It is based upon RHEL 7.7 upstream source code.

Linux kernel 5.0 released and here is how to install it

last updated in Categories Linux News

Linus Torvalds the creator and the principal developer of the Linux kernel announced the release of Linux kernel version 5.0. This release increases the major kernel version number to 5. from 4.x. The new change does not mean anything and does not affect programs in any way. From the mailing list:

Te overall changes for all of the 5.0 release are much bigger. But I’d like to point out (yet again) that we don’t do feature-based releases, and that “5.0” doesn’t mean anything more than that the 4.x numbers started getting big enough that I ran out of fingers and toes.

Raspberry $25 Pi 3 Model A+ Released – Complete specs and pricing

last updated in Categories Hardware, Open Source

The Raspberry Pi is a small single-board computer (SBC) developed by the Raspberry Pi Foundation. It supposes to promote the teaching of computer science, programming for kids and in developing countries. The new Raspberry Pi 3 Model A+ comes with 1.4GHz clock speed, 5GHz wireless networking and improved thermals of Raspberry Pi 3B+ in a smaller form factor. It costs $25.

400K+ Exim MTA affected by overflow vulnerability on Linux/Unix

last updated in Categories Linux News, Security

Exim is a free and open source message transfer agent (MTA) developed at the University of Cambridge. It is famous on Unix and Linux systems connected to the Internet. It is freely available under the terms of the GNU General Public Licence. There is a buffer overflow in base64d() of Exim MTA that allows an attacker to run code remotely. ALL versions of Exim MTA affected by overflow vulnerability i.e. CVE-2018-6789.
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How to record statistics about a Linux machine’s uptime

last updated in Categories Command Line Hacks, Hardware

Linux/Unix sysadmins have a weird obsession with server uptime. There is a xkcd comic devoted to this subject where a good sysadmin is an unstoppable force that it stands between the forces of darkness and your cat blog’s servers.
Fig.01: Devotion to Duty https://xkcd.com/705/
One can tell how long the Linux system has been running using the uptime command or w command or top command. I can get a report of the historical and statistical running time of the system, keeping it between restarts using tuptime tool. Like uptime command but with the more impressive output. Recently I discovered another tool called uptimed that records statistics about a machine’s uptime. Let us see how to get uptime record statistics using uptimed and uprecords on Linux operating system.

I put a cronjob in /etc/cron.{hourly,daily,weekly,monthly} and it does not run and how can I troubleshoot it?

last updated in Categories Cloud Computing, Howto, Open Source, Web Developer


Recently I created a simple shell script called backup.sh in /root/scripts directory to just backup MySQL database and dumped it to /nfs/mysql/ directory. I put a file (more like used the ln command to create a soft link ) in /etc/cron.hourly/ and it doesn’t run. There was no error in systemd log or cron log. Why is my cron job was not working, and here is how I troubleshoot it.