Question: I was installing Packstack and was hit with an error “error: md5 validation failed for PyYAML-3.11.zip; possible download problem?“. Below is the command I used to install Packstack. $ cd packstack && sudo python setup.py install The setup.py installed few packages and it failed while downloading PyYAML version 3.11….

Windows 10 is a huge hit, says Internet and reports from Microsoft. But wait, there are few serious bugs and privacy concerns surrounding Windows 10. I recently came across an article, that says Microsoft is monitoring everything you do with Windows 10 (such as Microsoft knows how long you use…

Question: I would like to know if there’s a command in Linux (may be in CentOS, RedHat or Fedora) that allows me to find out which CPU core is currently running a particular process? Answer: Yes, there are at least four ways that lets you identify the CPU core that’s currently running…

Question: I would like to know if there’s a command in CentOS that allows me to find which package an executable or file or library belongs to? For example, how can I find which package contains /usr/bin/sha256sum executable or which package contains a /usr/lib64/libnss3.so library file. Answer: You can use rpm -qf command…

Question: I would like to know the steps to change the default Timezone in Linux. I have CentOS 6.7 installed and the date command displays CST timezone as shown below $date Tue Dec 19 00:22:20 CST 2015 Can you explain me how to change CST to IST timezone in Linux? Answer: In…

Question: How to check if a particular website is using SHA1 or SHA2 Certificate? I would like to know the steps to check via web browsers and also using OpenSSL commands. How to check Signature Algorithm of SSL certificate using OpenSSL Command? The OpenSSL command shown below will fetch a SSL…

I recently updated WordPress to version 4.4 and found a new JavaScript loaded in the footer. It’s none other than wp-embed.js file. After googling, I understood that WordPress 4.4 comes with a feature (oEmbed consumer) that allows users to embed content from other sites – such as YouTube videos, tweets and…

XML-RPC in WordPress is an useful feature that allows you to remotely publish posts via mobile phones or tablet or Windows Live Writer. However, keeping XML-RPC enabled on your WordPress blog is always a risk. Recently, an attacker used xml-rpc on one of my WordPress blog to send some spam traffic…

Have you updated to WordPress 4.4 and not able to find “View Post” button in the editor window? Not to worry, as the button is now replaced with a clickable permalink (check out the below images). Well, few might see this change annoying in the latest version of WordPress, but I…

PHP thrown this error PHP Warning:  PHP Startup: Unable to load dynamic library wrong ELF class: ELFCLASS64, while installing Composer on my CentOS box having PHP version 5.3.3. Below is the complete error message: PHP Warning:  PHP Startup: Unable to load dynamic library ‘/usr/lib/php/modules/gd.so’ – /usr/lib/php/modules/gd.so: wrong ELF class: ELFCLASS64 in…

Composer is a dependency manager for PHP, which allows you to require all dependant libraries for a particular project. In layman terms, composer can bring in all dependant libraries required on a project by project basis and keeps them all at one place. You may read this article from PHILIP BROWN@culttt.com who…

Question: I have around 5,000 pending comments in my WordPress and most of those are spams. I would like to know if there’s a MySQL query that lets me to mass delete all of those? Answer: Yes, you can delete all the pending comments using MySQL query. All you need to do…

If you ever want to delete ssh-rsa keys in Linux, you just need to edit known_hosts file under .ssh folder. But on Windows? Well, this tutorial is just about that – removing or deleting outdated RSA keys from PuTTY on Windows operating system. Here’s a step by step guide to do…

Have you been waiting for this? At least, I had been. I’m not a big fan of uninstalling the entire OS to install latest version, but I had no option until CentOS 7 was released – it means, CentOS 7 comes with an in-place upgrade feature that allows you to…

Question: I was compiling Python from source and during ‘make install’, the installation failed with an error message as Sorry: UnicodeError: (“\\N escapes not supported (can’t load unicodedata module)”,). What could be the problem? Solution: I have solved this error couple of times during Python installation by uncommenting the line…

Question: I get SyntaxError: Missing parentheses in call to ‘print’ when I invoke/execute ‘preupg‘ command on my CentOS machine. What could be the issue? Here’s the snapshot of the error: # sudo preupg File “/usr/bin/preupg”, line 25 print ‘\nAssessment interrupted.’ ^ SyntaxError: Missing parentheses in call to ‘print’ Solution: According…

Question: I’m quite new to Python programming. I was trying to learn try, except statements in Python with a simple example – may be to open a new file and write few contents into it. While handling the exception using except, I get a Syntax error at the line ‘except IOError,…

I was trying to install a package using yum and hit with an error : GPG key retrieval failed: [Errno 5] OSError: [Errno 2] No such file or directory: ‘/etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL’. I understand that yum is trying to locate GPG keys for EPEL repository under /etc/pki/rpm-gpg/ and failed because of a missing file. Solution:…

Your Python installation does not support SSL? You need to compile it again after editing Setup.dist file located in the Python source directory. Let’s see how to do that. Before we begin, check if your existing Python installation supports OpenSSL as shown below: $ python In the python prompt, type…