performance

Bookmarks for 9 Dic 2015 from 12:09 to 16:26

These are my links for 9 Dic 2015 from 12:09 to 16:26:

  • One Thing Well | Let’s Encrypt – Let’s Encrypt is now in public beta and offers a command line tool that makes the process of getting and renewing certificates easy, but you have to run it as root, and it’s designed to rewrite your web server’s configuration files. Here’s a selection of alternative tools and clients:
  • Tsung – It can be used to stress HTTP, WebDAV, SOAP, PostgreSQL, MySQL, LDAP and Jabber/XMPP servers. Tsung is a free software released under the GPLv2 license. The purpose of Tsung is to simulate users in order to test the scalability and performance of IP based client/server applications. You can use it to do load and stress testing of your servers. Many protocols have been implemented and tested, and it can be easily extended. It can be distributed on several client machines and is able to simulate hundreds of thousands of virtual users concurrently (or even millions if you have enough hardware …). Tsung is developed in Erlang, an open-source language made by Ericsson for building robust fault-tolerant distributed applications. [ via http://onethingwell.org/post/134852940551/tsung ]
  • Internet Redundancy with ASA SLA and IPSec – PacketU – I’ve seen a lot of examples of redundant Internet connections that use SLA to track a primary connection. The logic is that the primary Internet connection is constantly being validated by pinging something on that ISP’s network and routing floats over to a secondary service provider in the event of a failure. I was recently challenged with how this interacted with IPSec. As a result I built out this configuration and performed some fairly extensive testing.

Bookmarks for 16 nov 2015 through 17 nov 2015

These are my links for 16 nov 2015 through 17 nov 2015:

  • Dkron – Distributed, fault tolerant job scheduling system – Dkron is a system service that runs scheduled jobs at given intervals or times, just like the cron unix service but distributed in several machines in a cluster. If a machine fails (the leader), a follower will take over and keep running the scheduled jobs without human intervention. Dkron is Open Source and freely available.
  • apache tuneup – Important to understand, this apache servers only one static image we use for the BI team. It does recieve and log a huge cookie and sends a 43 byte 1×1.gif image. Atention: It may not work right for dynamic web servers, as I use the mod_cache.
  • Gogs – Go Git Service – a painless self-hosted Git service – A painless self-hosted Git service. The goal of this project is to make the easiest, fastest, and most painless way of setting up a self-hosted Git service. With Go, this can be done with an independent binary distribution across ALL platforms that Go supports, including Linux, Mac OS X, Windows and ARM.

Bookmarks for 21 set 2015 through 24 set 2015

These are my links for 21 set 2015 through 24 set 2015:

  • IOWait. (Sysadmin’s bedtime horror story) – […] hope this helps someone out there. The last 3 days, I have had my server crash on me every 2-3 hours. At first I thought it would be a spike in the traffic, since I couldn’t find any crash reports from Apache, and there was a spike in the traffic at this time. So I increased the resources on the server. It crashed again, every 2-3 hours […] It wasn't my case but… who knows in the future?
  • Apache mod_deflate and mod_cache issues | Devon Hillard’s Digital Sanctuary – The Problem: Using Apache mod_deflate and mod_disk_cache (or other mod_cache) together can create far too many cached files. The Background: Apache is a web server with many different modules you can load in to enhance it. Two common ones are mod_deflate and mod_cache (or mod_disk_cache).
  • haskellcamargo/skype-unofficial-client · GitHub – (unofficial) Skype client built on top of node webkit [ via http://www.lffl.org/2015/09/skype-web-client-linux.html ]
  • dfletcher/tsws · GitHub – TSWS, A Totally Simple Web Server
  • Home | Lattice – Lattice aspires to make clustering containers easy. Lattice includes a cluster scheduler, http load balancing, log aggregation and health management. Lattice containers can be long running or temporary tasks which get dynamically scaled and balanced across a cluster. Lattice packages components from Cloud Foundry to provide a cloud native platform for individual developers and small teams.

Bookmarks for 29 mag 2015 through 10 giu 2015

These are my links for 29 mag 2015 through 10 giu 2015:

  • My Blog: AWS EC2 Auto Scaling: Basic Configuration – Our goal: Create an Auto Scaling EC2 Group in a single Availability Zone and use a HTTP status page as a Health Monitor for our Load Balancer and the Auto Scaling group instances. This exercise will show us some Auto Scaling basics and will be useful to understand the concepts beneath but the Auto Scaling Group will not automatically "scale" responding to external influence like Average CPU Usage or Total Apache Connections (This aspect is covered in this post: AWS EC2 Auto Scaling: External CloudWatch Metric). With the Auto Scaling configuration described here, we will obtain a web server cluster that can be increased and decreased in members with a simple Auto Scaling API call and we will transfer the monitoring role to the ELB to automatically replace failed EC2 instances or web servers.
  • Autoscaling with custom metrics « That’s Geeky – One of the appeals of cloud computing is the idea of using what you need when you need. One of the ways that Amazon provides for this is through autoscaling. In essence, this allows you to vary the number of (related) running instances according to some metric that is being tracked. In this article, we look at how you can trigger a change in the number of running instances using a custom Cloudwatch metric – including the setup of said metric, and a brief look at the interactions between the various autoscaling commands used.
  • Painless AWS Auto Scaling With EBS Snapshots And Capistrano – Boom – AWS (Amazon Web Services) auto scaling is a simple concept on the surface: You get an AMI, set up rules, and the load balancer takes care of the rest. However, actually getting it done is more complicated. Some choices are worse than others: you could bake an AMI (Amazon Machine Image) before you deploy, but that could add 10 minutes or more to each deployment. Some are dangerous: you could create an AMI after each deploy, but you run the risk that an auto scale even happens before your AMIs are done. Plus, you have a whole variety of AMIs deployed in at any given time. Some are similar to what we propose in this tutorial: you could push your code to S3 on each deploy and have user-data scripts that pull it down on each auto scaling event. However you slice it, to get auto scaling to fit into your development work flow in a transparent way takes careful thought and planning. We recently rolled out the following solution at CodePen. It keeps our AMIs static and our application ready for scaling on EBS (Elastic Block Store) snapshots. We can push code using Capistrano and let a few scripts distribute the ever-changing code base to our fleet of servers. I’d like to share the steps required to make it work. This series of posts will walk you through the steps required to build an auto-scaling infrastructure that stays out of your way.
  • coderwall.com : establishing geek cred since 1305712800 – Did you accidentally set node.normal[:foo][:bar] = 'something bad' in your chef recipe? Then you found that the node's normal attributes persisted between chef runs, and you really wanted to use the default attribute precedence level in your cookbook's attributes/default.rb file?

Bookmarks for 2 apr 2015 through 1 mag 2015

These are my links for 2 apr 2015 through 1 mag 2015:

  • Apache vs Nginx vs OpenLiteSpeed – As a hosting provider, we run hundreds of web servers with varying configurations. Some are tuned to work with large systems, some are tuned to work with lots of domains and some a tuned to be highly resource efficient. The “one size fits all” approach doesn’t work with web technology simply because the tools and the tasks vary so greatly.
  • Ratatype — Online Typing Tutor and Typing Lessons – Learn to type faster with Ratatype typing tutor. Take our typing lessons for free.
  • How do I assign issues to multiple users – JIRA 6.4.x – Atlassian Documentation – JIRA is designed so that issues must be assigned to a single individual to prevent tasks from being overlooked. A team lead or manager should assign issues out to individuals, or your users will pick from a list of issues that they have the option to take on. However, if you want to configure JIRA to allow issues to be assigned to multiple users there are a few option for doing so: Managing Issues via a Queue Managing Issues via Group Ownership Managing Issues via a User Account Managing Issue via Sub-Tasks
  • ONLYOFFICE™ Server Community Version – ONLYOFFICE™ – ONLYOFFICE™ Community Server is a freely downloadable open source software, distributed under the GNU Affero General Public License v.3. It comprises all the basic functional modules sufficient for comprehensive document and project management as well as any size team collaboration.
  • Building a Raspberry-Pi Stratum-1 NTP Server – As an experiment, I purchased one of the low-cost credit-card-size Raspberry Pi computers, and have configured it to run NTP (Network Time Protocol).  I have also used this board with a GPS receiver with pulse per second (PPS) output to make a stratum-1 NTP server, but as I know little of Linux, it has taken some time to achieve this aim!  There are some helpful Linux commands scattered throughout this page.  These notes are almost as much for my own records for the next time I need to visit this project, but I hope they may be helpful to others.[…] [ via MD on http://braindead.tumblr.com/post/115170631701 ]

Bookmarks for 30 mar 2015 through 31 mar 2015

These are my links for 30 mar 2015 through 31 mar 2015:

  • 5 easy tips to accelerate SSL – Unhandled expression – SSL is slow. These cryptographic algorithms eat the CPU, there is too much traffic, it is too hard to deploy correctly. SSL is slow. Isn’t it? HELL NO! SSL looks slow, because you did not even try to optimize it! For that matter, I could say that HTTP is too verbose, XML web services are verbose too, and all this traffic makes the website slow. But, SSL can be optimized, as well as everything!
  • Cybrary – Free Online IT and Cyber Security Training, Forever! – Cybrary is a free and open source, online information technology (IT) and cyber security training environment for the world. We are dedicated to keeping the world’s IT professionals prepared for this ever changing industry and its technologies. You can learn almost anything IT and security related for free, and you can help others to do the same. Take a look at what you can learn: Systems Administration Network Administration Cyber Security Our free IT training classes include everything from industry certifications such as Certified Ethical Hacker, CISSP and CCNA to advanced niche skill sets like advanced penetration testing and cloud administration. Our training includes instructional lectures, interactive lab demonstrations, exam study guides, white papers, case studies and more. [ via https://delicious.com/farmando]
  • Exploit Exercises – exploit-exercises.com provides a variety of virtual machines, documentation and challenges that can be used to learn about a variety of computer security issues such as privilege escalation, vulnerability analysis, exploit development, debugging, reverse engineering, and general cyber security issues. [ via https://delicious.com/farmando ]

Bookmarks for 27 feb 2015 through 28 feb 2015

These are my links for 27 feb 2015 through 28 feb 2015:

  • Excel: dieci errori da non fare – Excel è un programma molto utile, che fa risparmiare un sacco di tempo e di fatica a chi lo usa correttamente, ma che può facilmente trasformarsi in un buco nero del nostro tempo se usato male. Siccome mi capita di vedere che certi errori sono frequentissimi e fanno perdere un sacco di tempo inutilmente, elenco qui i più drammatici, a monito de li piccini.
  • websocketd – WebSockets the UNIX way Full duplex messaging between web browsers and servers
  • HTTP 2.0 – Tokyo – Google Slides –

Bookmarks for 28 ott 2014 through 29 ott 2014

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

Bookmarks for 25 set 2014 from 12:03 to 17:40

These are my links for 25 set 2014 from 12:03 to 17:40:

  • sebsauvage/rss-bridge – The RSS feed for websites missing it
  • debsecan – The debsecan program evaluates the security status of a host running the Debian operation system. It reports missing security updates and known vulnerabilities in the programs which are installed on the host. debsecan accesses the dpkg database and obtains a list of installed packages and their versions. This list is then evaluated against a feed of vulnerability information which ultimately comes from a database maintained by Debian's Testing Security Team . Various output formats are supported, including incremental reporting via email. Beginning with version 0.2, debsecan includes a script called debsecan-create-cron, which allows you to create a cron job which periodically sends you mail (once per day) when the security status of the system changes.
  • Barriers, Caches, Filesystems | monolight – With the recent proliferation of ext4 as the new “default” Linux filesystem there’s been much talk of write barrier support. The flurry of post-2.6.18 barrier related development in most storage subsystems has left some novice users and administrators perplexed. I hope I can clear it up a bit with this primer/refresher.
  • SMTP, testing via Telnet – FreeBSDwiki – When troubleshooting problems with SMTP service – your own, or others – it is frequently very helpful to be able to "speak" to the SMTP server directly, rather than going through a mail client which won't necessarily tell you exactly what the SMTP server is saying. You can easily do this with the telnet client. Note that many ISPs do not allow outbound connections on port 25 to any SMTP server but their own – if you get timeouts when trying to connect to port 25, you should try port 587, which is the standard ESMTP port. (Port 587 connections normally require SMTP AUTH, which is covered below.)

Bookmarks for 4 set 2014 through 5 set 2014

These are my links for 4 set 2014 through 5 set 2014:

  • tmux-plugins/tmux-resurrect – Restore tmux environment after a system restart. Tmux is great, except when you have to restart the computer. You lose all the running programs, working directories, pane layouts etc. There are helpful management tools out there, but they require initial configuration and continuous updates as your workflow evolves or you start new projects. tmux-resurrect saves all the little details from your tmux environment so it can be completely restored after a system restart (or when you feel like it). No configuration is required. You should feel like you never quit tmux. http://undeadly.org/cgi?action=article&sid=20140904174329
  • box/Anemometer – This is the Box Anemometer, the MySQL Slow Query Monitor. This tool is used to analyze slow query logs collected from MySQL instances to identify problematic queries.
  • SpamExperts/pyzor – Pyzor is a Python implementation of a spam-blocking networked system that use spam signatures to identify them.