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Keep It Simple: Bring Software Complexity Under Control

CORDIS News (12/19/12)

European Union-funded researchers working on the industrial deployment of advanced system engineering methods for high productivity and dependability (DEPLOY) project, have developed an approach for building software systems that is safer, less expensive, and more robust.  The research aims to improve traditional software engineering processes that are not equipped to handle the complexity and diversity of modern software systems.  "As more and more elements and more functionality are packed into systems, engineers say they are losing control of complexity and worry they won't be able to provide the quality assurances required," says University of Newcastle professor Alexander Romanovsky.  He says the DEPLOY project approach follows formal engineering methods, which are starting to gain acceptance among industry experts as a more efficient, practical way to develop complex software systems.  Formal engineering methods are based on mathematical mode…

Setting Up Network RAID1 With DRBD On Ubuntu 12.04

A Network software raid1Setting Up Network RAID1 With DRBD On Ubuntu 12.04 This tutorial shows how to set up network RAID1 with the help of DRBD on two Ubuntu 12.04 systems. DRBD stands for Distributed Replicated Block Device and allows you to mirror block devices over a network (like raid1 with 2 disks). This is useful for high-availability setups because if one node fails, all data is still available from the other node.
1 Preliminary Note We use two servers (both running the same version of linux in our case Ubuntu 12.04): server1.cofares.net (IP address 192.168.10.100)server2.cofares.net (IP address: 192.168.10.101) Both nodes have an unpartitioned second drive (/dev/sdb) with identical size (X GB) that I want to mirror over the network (network RAID1) with the help of DRBD. It is important that both nodes can resolve each other, either through DNS or through /etc/hosts, /etc/hosts would be a better choice (our 2 servers are on the same switch and local. You can modify /etc/hosts on…

GIT: Remove sensitive data

From time to time users accidentally commit data like passwords or keys into a git repo. While you can usegit rmto remove the file, it will still be in the repo's history. Fortunately, git makes it fairly simple to remove the file from the entire repo history. Change your files This step should be blatantly obvious, but some users still skip it. If you committed a password, change it! If you committed a key, generate a new one. If you commited private files remove them. Once the commit has been pushed you should consider the data to be compromised. Purge the file from your repo Now that the password is changed, you want to remove the file from history and add it to the.gitignore to ensure it is not accidentally re-committed. For our examples, we're going to removeRakefile from the GitHub gem repo. $ git clone https://github.com/defunkt/github-gem.git # Initialized empty Git repository in /Users/tekkub/tmp/github-gem/.git/# remote: Counting objects: 1301, done.# remote: Compressi…

Le Cnam Liban

cnamliban.cofares.net association de soutient au Cnam Liban, Université d'ambition laïque et populaire (mais pas populiste) référence de rigueur et d'exellence, pour tous les Libanais. Ceci est le blog de la communauté.