Bookmarks for 28 mar 2014 through 29 mar 2014

These are my links for 28 mar 2014 through 29 mar 2014:

  • LDAP org chart | bitcube.co.uk – For centralised authentication and authorisation, LDAP is the de-facto standard. Whether in its pure form on Unix or in Active Directory guise on Windows, everyone uses it. What many people don't realise is that you can store all sorts of useful (and not so useful) information in LDAP. One field which can be useful is the "manager" attribute. One of our customers use that and so we've written a small script to graph it using the excellent Graphviz tool. It will probably need customising for specific cases, however we hope that people find it useful nonetheless. If you want to alter the output, do have a look at the record format documentation.
  • Puppet errors explained | bitcube.co.uk – Puppet is a wonderful system automation tool, however the learning curve can be a little steep. We've collected some of the errors messages and "strange" behaviour you may come across together with explanations to help overcome these hurdles and boost adoption of this fabulous tool. If you have any useful errors and explanations, please do send them in and we'll update this article.
  • SCAP: Guide To The Secure Configuration of Red Hat Enterprise Linux 5 – This guide has been created to assist IT professionals, in effectively securing systems with Red Hat Enterprise Linux 5.
  • DNS Load Balancing and Using Multiple Load Balancers in the Cloud – [...] Load balancing in general is a complicated process, but there's some secret sauce in managing DNS along with multiple load balancers in the cloud. It requires that you draw from a few different sets of networking and “cloudy” concepts. In this second article in my best practices series (my first post covered how to use credentials within RightScale for storing sensitive or frequently used values), I'll explain how to set up load balancers to build a fault-tolerant, highly available web application in the cloud. Here's what you’ll need: Multiple A records for a host name in the DNS service of your choice Multiple load balancers to protect against failure [...]
  • gdnsd – gdnsd is an Authoritative-only DNS server which does geographic (or other sorts of) balancing, redirection, weighting, and service-state-conscious failover at the DNS layer. gdnsd is written in C using libev and pthreads with a focus on high performance, low latency service. It does not offer any form of caching or recursive service, and notably does not support DNSSEC. There's a strong focus on making the code efficient, lean, and resilient. The code has a decent regression testsuite with full branch coverage on the core packet parsing and generation code, and some scripted QA tools for e.g. valgrind validation, clang-analyzer, etc. The geographically-aware features also support the emerging EDNS Client Subnet draft for receiving more-precise network location information from intermediate shared caches.

Bookmarks for 25 mar 2014 through 28 mar 2014

These are my links for 25 mar 2014 through 28 mar 2014:

  • blblack/gdnsd – gdnsd is an Authoritative-only DNS server. The initial g stands for Geographic, as gdnsd offers a plugin system for geographic (or other sorts of) balancing, redirection, and service-state-conscious failover. The plugin system can also do things like weighted address/cname records. If you don't care about these features you can ignore them :).
  • How to Create and Apply Patches in GIT using diff and apply Command – Creating a patch in GIT is a great way to share changes that you are not yet ready to push to a public branch of a project.
  • Your own Dynamic DNS in 3 steps | The Nexus – This is a "niche" post: it will really only appeal to you if you have access to your own — or a friend's — name servers and want to use your own domain to track your dynamic IP addresses, such as your home router's. You will still have to buy your own domain, cheap if you go to internet.bs or namecheap.com. I hear that the latter even provide their own dynamic DNS service although I cannot tell you anything about its quality/flexibility. So, why this post? It's for you, my friends, budding entrepreneurs who wish to bootstrap your business and know that every cent counts. Maybe you feel that you could host your product's web site on a home computer. Maybe you need more control over what happens on that server. Or maybe you want to be able to log on to your development machine from anywhere in the world. Whatever your reasons, you're still here. So let's get started.
  • Apache – Prefork or Worker | Code Bucket – Apache is the most common and famous webserver. Everyone knows about apache and most of us also have hands on experience with apache. But few of us know that apcahe2 comes with 2 multi processing modules(MPMs): 1. Prefork 2. Worker
  • Ottimizzazione di Apache, dall’analisi ai parametri – [...] I recenti sviluppi nel campo della virtualizzazione hanno accelerato la moltiplicazione di ambienti virtuali vps a basso costo, molto convenienti ma a volte carenti dal punto di vista delle risorse di sistema. Molto spesso questi ambienti vengono utilizzati a scopo di testing o come ambienti di produzione all'interno dei quali viene implementato l'utilizzo di un web server. Apache, come ben sappiamo ,e uno dei web server piu diffusi e nella maggioranza dei casi rappresenta la scelta di default su un grandissimo numero di installazioni [...]

Bookmarks for 8 ago 2013 through 12 ago 2013

These are my links for 8 ago 2013 through 12 ago 2013:

  • Shuttle | A simple SSH shortcut menu for OS X – A simple SSH shortcut menu for OS X
  • Unix FAQ/shell Index
  • Portable Shell – Autoconf – When writing your own checks, there are some shell-script programming techniques you should avoid in order to make your code portable. The Bourne shell and upward-compatible shells like the Korn shell and Bash have evolved over the years, and many features added to the original System7 shell are now supported on all interesting porting targets.

Bookmarks for 15 gen 2013 through 16 gen 2013

These are my links for 15 gen 2013 through 16 gen 2013:

  • Simplify Advanced Shell Scripting With Ruby | AIX | IBM Systems Magazine | System p, System p5, Power System | Ruby, SSH, shell scripting, Bull Freeware, sysadmin, – IBM Systems Magazine – Ruby is just for experienced programmers. right? False! Originating in the mid-1990s, Ruby is a fantastic language, made popular recently by the Web application framework—Ruby on Rails. It’s a massively flexible and easy language to learn. You can find Ruby for AIX in the AIX Toolbox at the Bull Freeware. The script we’ll be creating will do the following:

     

    * Go through a large list of servers.
    * SSH them and determine whether the server is AIX.
    * If so, it will go through all disks, returning their type.
    * It will do all of this completely in parallel in batch at 25 sub-processes at a time.

  • Recovering a lost partition table with a VMFS volume | vInfrastructure Blog – Vi possono essere diversi motivi che portano alla perdita della tabella delle partizioni o alla sua corruzione. Nel caso di datastore VMFS le possibili cause sono: resignature da un altro sistema (ad esempio il backup server, nel caso funzioni in SAN mode), un errore umano (basta eseguire, su dischi condivisi, da vSphere Client un Datastore / Delete da un ESXi non ancora collegato al vCenter Server), o anche a causa di qualche problema lato storage (mi è capitato proprio questo caso di recente su uno storage entry level)[...]

    (Mi è capitato, ho seguito la kb di vmware e ne sono uscito. Comunque sto sudando ancora adesso…)

  • DataFart – DataFart lets you easily graph data from the command line.