Why?
Rate limiting an API is often required to ensure that clients do not abuse the available resources and that the API is reliably available when multiple clients are requesting data concurrently. Buckets can be created based on various parameters of an incoming request (eg. Authorization, IP address) to configure how requests are grouped for limiting.

Rate limiting functionality is already available in some proxies (eg. Nginx, HAProxy). However, they often use in-memory stores that make rate-limiting when running multiple proxies (e.g. for load balancing) unpredictable. Configuration for these limits also gets complex since it includes many actions such as routing, request/response re-writing, and rate-limiting.

Sphinx is not...
Sphinx is not focused on preventing Denial of Service (DoS) attacks or requests from malicious clients. The goal is to expose rate limiting information to clients and enforce balanced use by API clients.

Sphinx is not a request forwarding service. Sphinx only allows for very simplistic forwarding to a single host per instance of the rate limiter. Any advanced routing or request handling should be handled by a real proxy (eg. Nginx, HAProxy).

Sphinx is not an HTTPS terminator. This keeps the burden of configuring SSL certificates and security outside of Sphinx. Ideally, there is real load balancing and HTTPS termination before a request hits Sphinx.

According to Lifehacker a frozen Linux system that’s not responding to the Ctrl-Alt-Delete three-finger-salute can be restarted more safely than by pushing the power button, which is usually the next step.

Holding down Alt and SysRq (which is the Print Screen key) while slowly typing REISUB will get you safely restarted. REISUO will do a shutdown rather than a restart.

Sounds like either an April Fools joke or some very strange magic akin to the old BIOS beeps we used to use to diagnose PC faults so bad that nothing would boot. Wikipedia comes to the rescue with an in-depth listing of all the SysRq keys.

R: Switch the keyboard from raw mode to XLATE mode
E: Send the SIGTERM signal to all processes except init
I: Send the SIGKILL signal to all processes except init
S: Sync all mounted filesystems
U: Remount all mounted filesystems in read-only mode
B: Immediately reboot the system, without unmounting partitions or syncing
(Discovered originally here)

We have all experienced the limitations of the relational model and the operational burden of running a large fleet of databases. At PlanetScale, our vision is to build a database developers love without compromising on any of the database features required to run an application that can scale up as needed. To achieve this, we knew we needed a database engine with a track record of powering companies that deal with humongous amounts of data and traffic. That’s why we chose Vitess.

Free and open source software for video recording and live streaming.

Mind maps are diagrams used to organize information visually in hierarchical ways that show relationships among the elements that make up the map.

If you connect to remote computers over the Internet, it is a pretty good chance you use some form of SSH or secure shell. On Linux or Unix you’ll use the ssh command. Same goes for Linux-lik…

An easy to use editor for crontab schedules.

At this stage of our Bash basics series, it would be hard not to see some crossover between topics. For example, you have already seen a lot of brackets in the examples we have shown over the past several weeks, but the focus has been elsewhere.

For the next phase of the series, we’ll take a closer look at brackets, curly, curvy, or straight, how to use them, and what they do depending on where you use them. We will also tackle other ways of enclosing things, like when to use quotes, double-quotes, and backquotes.

This week, we're looking at curly brackets or braces: {}.

The dig command is an incredibly powerful tool for querying DNS records. Dig stands for Domain Information Groper and is the utility of choice for most DNS administrators working on Linux. It can be used to confirm DNS entries, get your public IP address from the command line, troubleshoot DNS issues and get information about a DNS zone.

Dig is part of the BIND (Berkely Internet Name Domain) software utilities (bind-utils). Although not installed by default, it is available on nearly all Linux distributions by installing the bind-utils package or Red Hat variants or dnsutils on Debian based distros.

LOG MANAGEMENT FOR ALL
Built to open standards, Graylog’s connectivity and interoperability seamlessly collects, enhances, stores, and analyzes log data.

Déjà Dup (day-ja-doop) is a simple backup tool. It hides the complexity of doing backups the Right Way (encrypted, off-site, and regular) and uses duplicity as the backend.

a free hex editor / disk editor for Linux, Windows and MacOSX

Okteta is a simple editor for the raw data of files. This type of program is also called hex editor or binary editor.

This article focuses on software which emulates home computers, a class of personal computer which reached the market in the late 1970s, and became immensely popular in the following decade, selling many millions of units. Leading home computer companies included Commodore, Sinclair, Atari, Apple, Acorn, Tandy Radio Shack, and Amstrad.

In this article, you will learn about some free, open source, and exciting, text-based tools or utilities to help you do more with boredom on the Command line.

Most of us use online services like Gmail, Dropbox, Skype, Evernote etc. on a daily basis without having control over the service. However, now it’s easier than ever to find a self-hosted alternative to your favorite online service and have complete control over it. In this article, we will share a huge list of self-hosted alternatives to popular online services.

Find alternatives to:
Google Analytics
WordPress, Joomla, Drupal
Google Drive, OneDrive, Dropbox
Gmail, Yahoo Mail
Google Reader, Feedly
Google Docs, Microsoft Office Online
Evernote, OneNote, Google Keep
Skype, Slack, HipChat
Trello
GitHub
Google Calendar, Apple Calendar, Mozilla Thunderbird’s Calendar
Zendesk, UserVoice, Freshdesk
Disqus, Facebook Comments, IntenseDebate
Facebook, Twitter
Wikia, Wikipedia
Shopify, Gumroad, Sellfy
LastPass
Imgur, Flickr, ImageShack
SugarCRM, Zoho, Nutshell
TinyURL, goo.gl, CloudApp

One of the reasons why we love our servers (and we love them a lot!) is that everyone gets full root access. This means that you are in full control over your server while still having the dedicated, EPIC 24/7 support. You can install any software and application you want to. There are many options to choose from when it comes to self-hosted alternatives to hosted services. But first off, what are the differences?

A disclaimer: we may be a bit biased, as we really love and support the open source community. We are always open to criticism and suggestions, though. So let us know in the comments if there’s anything you think we should change.

Do you want to block visitors by country?
Select the countries you want to block, IP address version (IPv4 or IPv6), output format and press the "Download" button.

The output formats supported are Apache .htaccess, Linux iptables, CIDR, Netmask, Inverse Netmask, IIS web.config, Cisco ACL, PeerGuardian2, network-object, Cisco bit bucket, Juniper Junos and MicroTik. Please find the details below:

Timeshift is a GTK3-based, open source, system restore utility which takes incremental snapshots of the system using rsync and hard-links. These snapshots can be restored at a later date to undo all changes that were made to the system after the snapshot was taken. Snapshots can be taken manually or at regular intervals using scheduled jobs.

Nmon is short for “Nigel’s Monitor”. It’s a systems administrator, tuner, and benchmark all wrapped up in an easy-to-use tool. The utility displays performance information on the CPU, memory, network, disks (mini graphs or numbers), filesystems, NFS, top processes, resources (Linux version & processors) and more.

Krusader is an advanced, twin-panel (commander-style) file manager designed for KDE Plasma. Krusader also runs on other popular Linux desktop environments such as GNOME.