OpenSSH – Wikibooks, open books for an open world – The OpenSSH suite provides secure remote access and file transfer. Since its initial release, it has grown to become the most widely used implementation of the SSH protocol. During the first ten years of its existence, ssh has largely replaced older corresponding unencrypted tools and protocols. The OpenSSH client is included by default in most operating system distributions, including OS X, Linux, BSD and Solaris. Any day you use the Internet, you are using and relying on dozens if not hundreds of machines operated and maintained using OpenSSH. A survey in 2008 showed that of the SSH servers found running, just over 80% were OpenSSH.  OpenSSH was first released towards the end of 1999. It is the latest step in a very long and useful history of networked computing, remote access and telecommuting. This book is for fellow users of OpenSSH to help them save effort and time through using OpenSSH, and especially SFTP, where it makes sense to use it.
ssl-cert-check » Linux Shtuff – [...] Digital certificates have become an essential part of Internet commerce, and are widely used to verify the identity of clients and servers. All digital certificates contain an expiration date which most client and server applications will check before using the certificates contents. If a client or server application detects that a certificate has expired, one or more implementation specific actions (e.g., abort connection, check or update a revocation list, alert user, etc.) are typically performed.[...]
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.
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.
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.
ZetCode, tutorials for programmers – ZetCode brings tutorials for programmers in various areas. The main are Graphics User Interface, databases and programming languages. The website's mission is to provide competent, quick and easy to understand tutorials for modern-day technologies.