Posts By: jonny

MySQL Percona Slave Replication Change Channel Name

I had inadvertently set up slave replication using the wrong channel name – which is a minor issue except that it caused some issues with an already configured Nagios check. To ‘change’ the channel name I stopped the slave process, removed all the slave definitions and used ‘CHANGE MASTER’ to re-create the slave from the… Read more »

Mount Files Virtually via Dell iDRAC

Use fallocate to create a new 300 MB file : fallocate -l 300M disk_image.img Create an ext4 file system within the image file: mkfs.ext4 disk_image.img Create a mount point: mkdir /mnt/disk_image mount it: mount -t auto -o loop disk_image.img /mnt/disk_image Then on the Dell iDRAC use the ‘Virtual Media’ menu to ‘Map Removable Disk…’  :… Read more »

Docker jasonrivers/nagios Permissions Problem

I was running this docker image proxied via traefik but I was receiving an error message in the Nagios web interface: docker nagios Error: Could not read object configuration data And in the logs from the container: container_name | Warning: File ‘/opt/nagios/var/perfdata.log’ could not be opened – service performance data will not be written to… Read more »

Determine Dell Hard Disk Location from Linux

On a Dell server I needed to determine the physical hard drive location for a faulty disk. Within the operating system the disk was mounted as /dev/sdk so I ran: udevadm info –query=all –name=/dev/sdk And from the output I could correlate this with the information in the iDRAC: So in this example disk 10 on… Read more »

Dell racadm on Linux

I’m currently using Linux Mint and wanted to communicate with the iDRAC interfaces on Dell servers. Install racadm: sudo echo ‘deb xenial openmanage’ | sudo tee -a /etc/apt/sources.list.d/ sudo gpg –keyserver –recv-key 1285491434D8786F gpg -a –export 1285491434D8786F | sudo apt-key add – sudo apt-get update sudo apt-get install srvadmin-idracadm8 Test with: /bin/racadm -R… Read more »

Command Line Optimise JPEG image

This command significantly improved file size on disk although the quality value can be increased to adjust the image quality versus file size: convert input-file.jpeg -sampling-factor 4:2:0 -strip -quality 60 -interlace JPEG -colorspace RGB output-file-60.jpeg  

Cropping / Masking a Video for Kdenlive

I was helping a friend with creating a video and we need to mask out the distracting content around the video subject. If I had this problem with a static image I would use Gimp and the ‘Crop’ tool but I couldn’t find anything in Kdenlive to allow me to crop out a small square… Read more »

Managing RDP Remote Desktop Sessions/Users

RDP Session Manager

It took me a little digging to re-discover the name of this tool that allows remotely logging RDP users off from other servers so I thought I would write it down in case I need a reminder. The command to run is: tsadmin.msc Or it can be added directly from the MMC.

Laravel Quick Start

Quick reminder of steps to setup a Laravel project on Ubuntu/Linux Mint and similar. First install composer: sudo apt install composer Install PHP dependencies: sudo apt install php-cli-prompt php-common php-composer-semver php-composer-spdx-licenses php-fpm php-json-schema php-mysql php-symfony-console php-symfony-filesystem php-symfony-finder php-symfony-process php7.0-cli php7.0-common php7.0-fpm php7.0-gd php7.0-json php7.0-mbstring php7.0-mcrypt php7.0-mysql php7.0-opcache php7.0-readline php7.0-xml php7.0-zip php7.0-gd php7.0-mbstring php7.0-mcrypt php7.0-mysql   Use composer to create your Laravel project: composer create-project –prefer-dist laravel/laravel myprojectname Install composer.json packages: composer install Generate a key for your new project into the .env file: php artisan key:generate Amend the .env file with database details and anything else you want to customise. You may want to install mysql with sudo apt install mysql-server Auth Scaffolding… Read more »