Category Archives: Linux

Fedora Linux: LVM Single Drive to LVM RAID 1 Mirror Migration

By | March 3, 2017

All started when I wanted to have a true HA configuration for the server nodes. That implies that not only the storage of each server is a RAID10 setup, but also the boot and root resources are in a RAID1 configuration. I started to use an old and known tutorial to convert from standard installation… Read More »

Relax and Recover with bareos

By | June 30, 2015

A good way to backup the OS of the servers is to use rear Relax and Recover. Following are the steps to ensure that we have a proper rescue data set for both servers. STEP 1: Install rear from the Fedora repo on both nas1 and nas2 [root@nas1 ~]# dnf install rear [root@nas2 ~]# dnf… Read More »

Manipulate PDFs with gostscript

By | June 28, 2015

Basic Usage Convert PostScript to PDF: gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dQUIET -dBATCH -sOutputFile=fileout.pdf filein.ps Merge/combine PDF and/or PostScript files: gs -q -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=fileout.pdf \ filein.ps filein2.pdf Extract a page from a PostScript or a PDF document: gs -q -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -dFirstPage=3 -dLastPage=3 \ -sOutputFile=fileout.pdf filein.ps Additional Options PDF optimization level selection… Read More »

Linux command line tips 1

By | July 13, 2015

The Linux command line environment is very powerful and full of very useful command line instructions that are ignored by a lot o people. Following are some of the discovered commands I find very usefull: The “ls like” group: List all the usb devices: [root@localhost ~]# lsusb Bus 004 Device 002: ID 8087:0024 Intel Corp.… Read More »

USB Wireless interface on Fedora Linux

By | February 9, 2017

I am planning to deploy a test openStack infrastructure, “Minimal architecture example with legacy networking (nova-network)”, on the 2 x Hp MicroServer Gen 8 setup from my home data centre. The nova-network architecture needs at least two nodes and on each node a minimal of two network interfaces must be available. The HP MicroServers have… Read More »

Convert an existing 2 disk RAID 1 to a 4 disk RAID 10

By | December 7, 2015

When you want to have a secure set-up for your data storage having only two disks available a LVM over a RAID 1 set-up looks like the best solution. When an upgrade is necessary then having two separate RAID 1 based LVMs is no longer so appealing. To keep the same reliability of a disk… Read More »

“A” Rating Security – Strong SSL Security WordPress Blog

By | May 26, 2017

This should have been one of the first posts of this blog, because deals with the actual setup of the blog. To install a secure Blog is not an easy task. You can take the easy route and host your blog on a blogging site and hope that they will do a good pro bono… Read More »

Disable WebRTC to hide real IP when on a VPN

By | February 9, 2017

According to Daniel Roesler there is a privacy issue even if on VPN due to WebRTC. Your real IP can be disclosed by WebRTC. He made also a test page for this WebRTC test page. There is already a fix for your browsers : Firefox: Disable WebRTC Chrome: ScriptSafe    

voina.org Internet Speed

By | February 9, 2017

The standard connection from UPC Romania with my subscription 200Mbps/6Mbps. Good download crappy upload. I just found out there is a new 500Mbps/25Mbps plan in my city , Cluj-Napoca. I am going to try it asap. I am wondering how will my router cope with that. Linksys E4200 has a tested WAN to LAN Throughput… Read More »

Monitoring Fedora servers with NAGIOS

By | February 15, 2017

This is a description of the installation process of NAGIOS monitoring on two Fedora21 based servers. Choose one server as the main nagios host. Lets call it nas1. Add nagios users , group and add apache as member in the nagios group: # useradd nagios # groupadd nagcmd # usermod -a -G nagcmd nagios #… Read More »