Linux : error processing package nginx on Debian

Having this error trying to install Nginx on Debian Linux 8? dpkg: error processing package nginx (–configure): dependency problems – leaving unconfigured Errors were encountered while processing: nginx-full nginx E: Sub-process /usr/bin/dpkg returned an error code (1) This is a known behaviour if you have Apache or another Web server installed and running. The problem… Read More »

Linux : How to tune up receive (TX) and transmit (RX) buffers on network interface

Modern and performance/server grade network interface have the capability of using transmit and receive buffer description ring into the main memory. They use direct memory access (DMA) to transfer packets from the main memory to carry packets independently from the CPU. The usual default buffering values for regular desktop NICs are 256 or 512 bytes. High… Read More »

Linux : Edit Grub2 settings on RHEL/CentOS 7

RedHat / CentOS 7 is now shipped with Grub2 which require a different approach than the well known legacy Grub. To modify Grub2 settings or kernel parameters, edit the following file : /etc/default/grub Then regenerate the Grub config as followed : grub2-mkconfig -o /boot/grub2/grub.cfg

Windows : How to enable the legacy boot loader

Since Windows 8, everything is now Metro, not just the start menu, but the boot loader too! Fortunately, there is a command to disable the Metro boot loader and enable the legacy one. To do so, you will need to open the command line utility as administrator and use the following command : bcdedit /set… Read More »

ScreenOS : How to reset Juniper SSG to factory default

Here is the two procedures to reset your Juniper SSG ScreenOS device. The first method (if you have the password for your device) and serial connection to your device, you can do a software reset as followed. 1. Get your device serial number using the following command (or by reading the label on your device)… Read More »

Web : Firefox error code sec_error_reused_issuer_and_serial

You may ran into the following issue with Firefox browsing a SSL Web site using self generated certificate : sec_error_reused_issuer_and_serial The cause is that the self generated certificate of the site you are browsing have the same serial number of a previously stored certificate (another Web site you already visited and manually added an exception… Read More »

Category: Web

Linux : Essentials MySQL Admin CLI commands

Here is a quick list of useful commands for any MySQL database administrator. Show the server full status : mysqladmin -u root -p extended-status You may also sort specific information with “grep” as followed : mysqladmin -u root -p extended-status | grep Threads Show the current running process and queries (remove “-i 1” to display… Read More »

VMware : How to enable and set SNMP community on ESXi

VMware ESXi hypervisor have some great SNMP capability, whatever to gather information status of your hardware, monitoring or statistic usage of your resources. Follow these easy steps to enable such feature. 1. Enable SSH from the vSphere client and connect to it using your favorite terminal application : Configuration tab > Security Profile > Services >… Read More »