Posts By: jonny

Fido U2F Security Key

FIDO U2F Key Opening

So I ordered a FIDO U2F Security Key from a French company ‘Plug-Up’ to have a little play.  It is used in 2-factor authentication so when logging in to a service you first enter your username and password and if correct your are prompted for your second factor (a code sent by SMS or a… Read more »

Environment Modules

Environment Modules allow for management of environment variables  when using multiple compilers, multiple libraries, or even versions of applications that you might need to run. Rather than change $PATH, $LD_LIBRARY_LOAD, or $MANPATH for each you can use Environment Modules to handle the path changes to ensure you run the appropriate version correctly. Installation On CentOS… Read more »

Saving Streaming Video with VLC

VLC Convert Video Stream

I was asked by a relative if a live video stream could be saved for later viewing. I found the (m3u8) address for the live video stream by right-clicking the link on the website and used this in VLC. VLC is freedom software available from the VLC website. From the VLC menu bar I chose… Read more »

Server Technology Sentry Switched CDU

Sentry CDU

A few notes for future reference. I am playing with a power distribution unit from Server Technology  – Model CW-16VE-P32M Initially to configure the device I plugged both the Cabinet Distribution Unit (CDU) unit and a laptop into a switch, setting the IP address to the same subnet as the unit. I set the laptop… Read more »

Favicon Generator

Note to Self: The service at is great for generating favicon’s and icons for other mobile platforms.    

Deploying a Web Project from Gitlab

gitlab deploy hooks

I wanted to automatically deploy a web project when any updates are pushed to the gitlab repository. To do so I added a ‘Web Hook’. The Web Hook calls a URL in response to ‘push’ events. I created a PHP page to be called by the Web Hook: So in response to push events gitlab_hook.php… Read more »

Huge Pages in CentOS 6

centos logo

To check the size and amount of Huge Pages use:

This should so something like:

To change the number of HugePages use the following:

This would allocate 2560x2048kB = 5GB

To check the impact on memory:

Reset Huge Pages The change can be applied permanently in /etc/sysctl.conf but to… Read more »

Filezilla is Dead – Killed by Malware

With a heavy heart I can no longer recommend FileZilla.For years I had pointed users to Filezilla for several reasons including availability on multiple platforms and support for FTPS. I have now been informed that Windows users who download FileZilla via Sourceforge are getting an installer that tries to install crapware. Filezilla are aware of… Read more »

Building Slurm Scheduler RPM Packages

centos logo

Download the slurm tarball from Install dependencies:

Build the RPM:

After 5 minutes compiling this will create RPMs in the directory: ~/rpmbuild/RPMS/x86_64/ for me this was /root/rpmbuild/RPMS/x86_64/ The created RPMs were as follows: slurm-14.03.10-1.el6.x86_64.rpm slurm-pam_slurm-14.03.10-1.el6.x86_64.rpm slurm-sjobexit-14.03.10-1.el6.x86_64.rpm slurm-slurmdb-direct-14.03.10-1.el6.x86_64.rpm slurm-devel-14.03.10-1.el6.x86_64.rpm slurm-perlapi-14.03.10-1.el6.x86_64.rpm slurm-sjstat-14.03.10-1.el6.x86_64.rpm slurm-sql-14.03.10-1.el6.x86_64.rpm slurm-munge-14.03.10-1.el6.x86_64.rpm slurm-plugins-14.03.10-1.el6.x86_64.rpm slurm-slurmdbd-14.03.10-1.el6.x86_64.rpm slurm-torque-14.03.10-1.el6.x86_64.rpm I then added these RPM files to… Read more »

You (root) are not allowed to access to (crontab) because of pam configuration

I have obviously messed something up with my PAM configuration and received the following error message:

To get around this I amended the file:

And added a line for the root user as follows:

before the final deny line: