**A curated list of amazingly awesome Free and Open-Source sysadmin resources.** Please read the [Pull Request template](./.github/PULL_REQUEST_TEMPLATE.md) if you wish to add software and consider [donating](https://github.com/n1trux/awesome-donations) to the FLOSS projects you use regularly. Please consider contributing to fix one of the pinned [issues](https://github.com/awesome-foss/awesome-sysadmin/issues) if your time allows.
- [Bolt](https://puppet.com/products/bolt) - You can use Bolt to run one-off tasks, scripts to automate the provisioning and management of some nodes, you can use Bolt to move a step beyond scripts, and make them shareable.
- [Dar](http://dar.linux.free.fr/) - Which stands for Disk ARchive, is a robust and rich featured archiving and backup software of the tar style. ([Source Code](https://github.com/Edrusb/DAR)) `GPL-2.0``C++`
- [EasyBuild](https://easybuild.readthedocs.org/en/latest/) - EasyBuild builds software and modulefiles for High Performance Computing (HPC) systems in an efficient way.
- [environment-modules Lmod](https://www.tacc.utexas.edu/research-development/tacc-projects/lmod) - Lmod is a Lua based module system that easily handles the MODULEPATH Hierarchical problem.
- [HPCBIOS](http://hpcbios.readthedocs.org/en/latest/) - HPCBIOS is an effort to setup a common, well-documented and reproducible, environment spanning across multiple HPC systems & sites, *inclusive* of documentation.
- [Spack](https://spack.io/) - A flexible package manager that supports multiple versions, configurations, platforms, and compilers.
- [Eggdrop](http://www.eggheads.org/) - The oldest Internet Relay Chat (IRC) bot still in active development. ([Source Code](https://github.com/eggheads/eggdrop)) `GPL-2.0``C`
- [Errbot](http://errbot.io/) - a plugin based chatbot designed to be easily deployable, extensible and maintainable. ([Source Code](https://github.com/errbotio/errbot)) `GPL-3.0``Python`
- [Cobbler](http://cobbler.github.io/) - Cobbler is a Linux installation server that allows for rapid setup of network installation environments. ([Source Code](https://github.com/cobbler/cobbler))
- [BOSH](http://bosh.io/docs/) - IaaS orchestration platform originally written for deploying and managing Cloud Foundry PaaS, but also useful for general purpose distributed systems.
- [Cloud Foundry](https://www.cloudfoundry.org/) - A Platform-as-a-Service suite to provide the orchestration services that make distributed apps a powerhouse of awesomeness.
- [Cloudify](http://getcloudify.org/) - TOSCA-based cloud orchestration software platform written in Python and YAML.
- [CloudSlang](http://www.cloudslang.io/) - Flow-based orchestration tool for managing deployed applications, with Docker capabilities.
- [Genesis](https://github.com/starkandwayne/genesis) - A template framework for multi-environment BOSH deployments.
- [Juju](https://jujucharms.com/) - Cloud orchestration tool which manages services as charms, YAML configuration and deployment script bundles.
- [Kubernetes](http://kubernetes.io/) - Orchestration system for Docker containers - ([Source Code](https://github.com/kubernetes/kubernetes), [Documentation](http://kubernetes.io/docs/)) `Apache-2.0``Go`
- [MCollective](https://puppet.com/mcollective) - Ruby framework to manage server orchestration, developed by Puppet labs.
- [Nomad](https://www.nomadproject.io) - Simple and flexible orchestrator for Docker, Podman, executables, Java, and QEMU - ([Source Code](https://github.com/hashicorp/nomad), [Documentation](https://www.nomadproject.io/docs)) `MPL-2.0``Go`
- [Overcast](http://andrewchilds.github.io/overcast/) - Deploy VMs across different cloud providers, and run commands and scripts across any or all of them in parallel via SSH.
- [Salt](http://saltstack.com/) - Fast, scalable and flexible systems management software written in Python/ZeroMQ.
- [Spruce](https://github.com/geofffranks/spruce) - A tool that merges separate YAML files into one. Works well with [Genesis](https://github.com/starkandwayne/genesis).
- [StackStorm](https://stackstorm.com/) - Event Driven Operations and ChatOps platform for infrastructure management. Written in Python.
- [Terraform](https://www.terraform.io/) - Terraform works with many cloud providers and creates infrastructure from code.
- [Gerrit](https://www.gerritcodereview.com/) - Based on the Git version control, it facilitates software developers to review modifications to the source code and approve or reject those changes.
- [Phabricator](http://phabricator.org/) - Code review tool build by facebook and used by WikiMedia, FB, dropbox etc. Comes with an integrated wiki, bug tracker, VC integration and a CLI tool called arcanist.
- [Review Board](https://www.reviewboard.org/) - Available as free software under the MIT License.
- [Concourse](https://concourse-ci.org/) - Concourse is a CI tool that treats pipelines as first class objects and containerizes every step along the way. ([Demo](https://ci.concourse-ci.org/), [Source Code](https://github.com/concourse/concourse)) `Apache-2.0``Go`
- [drone](https://drone.io/) - Drone is a Continuous Delivery platform built on Docker, written in Go. ([Source Code](https://github.com/drone/drone)) `Apache-2.0``Go`
- [Factor](http://www.factor.io/) - Programmatically define and run workflows to connect configuration management, source code management, build, continuous integration, continuous deployment and communication tools. ([Source Code](https://github.com/factor-io/factor)) `MIT``Ruby`
- [GolangCI](https://golangci.com/) - Open Source automated code review service for Go integrated with GitHub pull requests. ([Source Code](https://github.com/golangci/golangci)) `AGPL-3.0``Go`
- [PHP Censor](https://github.com/php-censor/php-censor) - Open source self-hosted continuous integration server for PHP projects. `BSD-2-Clause``PHP`
- [PHPCI](https://www.phptesting.org/) - Free and open source continuous integration specifically designed for PHP. ([Source Code](https://github.com/block8/phpci)) `BSD-2-Clause``PHP`
- [werf](https://werf.io/) - Open Source CI/CD tool for building Docker images and deploying to Kubernetes via GitOps. ([Source Code](https://github.com/werf/werf)) `Apache-2.0``Go`
- [Woodpecker](https://woodpecker-ci.org/) - Community fork of Drone that uses Docker containers. ([Source Code](https://github.com/woodpecker-ci/woodpecker)) `Apache-2.0``Go`
- [Froxlor](https://froxlor.org/) - Lightweight server management software with Nginx and PHP-FPM support. ([Source Code](https://github.com/Froxlor/Froxlor/)) `GPL-2.0``PHP`
- [ISPConfig](http://www.ispconfig.org) - Manage Linux servers directly through your browser. ([Source Code](https://git.ispconfig.org/ispconfig/ispconfig3)) `BSD-3-Clause``PHP`
- [Sentora](http://sentora.org/) - Open-Source Web hosting control panel for Linux, BSD (fork of ZPanel). ([Source Code](https://github.com/sentora/sentora-core)) `GPL-3.0``PHP`
- [VestaCP](http://vestacp.com/) - Open-Source hosting control panel. ([Source Code](https://github.com/serghey-rodin/vesta)) `GPL-3.0``PHP/Shell/Other`
- [Virtualmin](http://www.virtualmin.com/) - Powerful and flexible web hosting control panel for Linux and BSD systems. ([Source Code](https://github.com/virtualmin)) `GPL-3.0``Shell/Perl/Other`
- [Webmin](http://www.webmin.com/) - Web-based interface for system administration for Unix. ([Source Code](https://github.com/webmin/webmin)) `BSD-3-Clause``Perl`
- [Capistrano](http://capistranorb.com/) - Deploy your application to any number of machines simultaneously, in sequence or as a rolling set via SSH (rake based).
- [Fabric](http://www.fabfile.org/) - Python library and cli tool for streamlining the use of SSH for application deployment or systems administration tasks.
- [Mina](http://nadarei.co/mina/) - Really fast deployer and server automation tool (rake based).
- [munki](https://www.munki.org/munki/) - Webserver-based repository of packages and package metadata, that allows macOS administrators to manage software installs.
- [Vlad the Deployer](https://github.com/seattlerb/vlad) - Deployment automation (rake based).
- [DrawThe.Net](http://go.drawthe.net/) - Javascript tool that uses a YAML-formatted input to programmatically create large, complex, and visually solid diagrams.
- [Mermaid](https://mermaid-js.github.io/mermaid-live-editor/) - Javascript module with a unique, easy, shorthand syntax. Integrates into several other tools like Grafana.
- [Go IPFS](https://github.com/ipfs/go-ipfs) - Implementation of [IPFS](http://ipfs.io/), a global, versioned, peer-to-peer filesystem that seeks to connect all computing devices with the same system of files.
- [HDFS](http://hadoop.apache.org/) - Distributed, scalable, and portable file-system written in Java for the Hadoop framework.
- [Minio](https://minio.io/) - Minio is an open source object storage server compatible with Amazon S3 APIs. ([Source Code](https://github.com/minio/minio)) `AGPL-3.0``Go`
- [OpenAFS](http://www.openafs.org/) - Distributed network file system with read-only replicas and multi-OS support.
- [Perkeep](https://perkeep.org/) (née Camlistore) - A set of open source formats, protocols, and software for modeling, storing, searching, sharing and synchronizing data.
- [SheepDog](https://sheepdog.github.io/sheepdog/) - A distributed Blockdevice, Rest, QEMU and distributed Filesystem storage.
- [TahoeLAFS](https://tahoe-lafs.org/trac/tahoe-lafs) - secure, decentralized, fault-tolerant, peer-to-peer distributed data store and distributed file system.
- [XtreemFS](http://www.xtreemfs.org/) - XtreemFS is a fault-tolerant distributed file system for all storage needs.
- [DNSControl](https://stackexchange.github.io/dnscontrol/) - Synchronize your DNS to multiple providers from a simple DSL. ([Source Code](https://github.com/StackExchange/dnscontrol)) `MIT``Go/Docker`
- [DomainMOD](https://domainmod.org) - Manage your domains and other internet assets in a central location. ([Source Code](https://github.com/domainmod/domainmod.git)) `GPL-3.0``PHP`
- [Notepad++](https://notepad-plus-plus.org/) - GPLv2 multi-language editor with syntax highlighting for Windows.
- [TextMate](https://github.com/textmate/textmate/) - A graphical text editor for OS X.
- [Vim](http://www.vim.org) - A highly configurable text editor built to enable efficient editing.
- [VSCodium](https://github.com/VSCodium/vscodium) - An open source cross-platform extensible code editor based on [VS Code by Microsoft](https://code.visualstudio.com/) removing their non-free additions.
- [389 Directory Server](https://www.port389.org/) - Enterprise-class Open Source LDAP server for Linux. ([Source Code](https://github.com/389ds/389-ds-base)) `GPL-3.0``C`
- [Apache Directory Server](https://directory.apache.org/apacheds/) - Extensible and embeddable directory server, certified LDAPv3 compatible, with Kerberos 5 and Change Password Protocol support, triggers, stored procedures, queues and views. ([Source Code](https://github.com/apache/directory-server)) `Apache-2.0``Java`
- [FreeIPA](https://www.freeipa.org/) - Integrated security information management solution combining Linux (Fedora), 389 Directory Server, Kerberos, NTP, DNS, and Dogtag Certificate System (web interface and command-line administration tools). ([Source Code](https://pagure.io/freeipa)) `GPL-3.0``Python/C/JavaScript`
- [FreeRADIUS](https://freeradius.org/) - Multi-protocol policy server (radiusd) that implements RADIUS, DHCP, BFD, and ARP and associated client/PAM library/Apache module. ([Source Code](https://github.com/FreeRADIUS/freeradius-server)) `GPL-2.0``C`
- [lldap](https://github.com/nitnelave/lldap) - Light (simplified) LDAP implementation with a simple, intuitive web interface and GraphQL support. `GPL-3.0``Rust`
- [OpenID Connect](http://openid.net/developers/libraries/) - A Simple Identity layer on top of OAuth 2.0.
- [OSIAM](http://osiam.github.io/) - Secure identity management solution providing REST based services for authentication and authorization.
- [Pomerium](https://www.pomerium.io/) - An identity and context aware access-proxy inspired by BeyondCorp.
- [Samba](https://www.samba.org/) – Active Directory and CIFS protocol implementation.
- [Smallstep Certificates](https://smallstep.com/certificates/) - A private certificate authority (X.509 & SSH) and related tools for secure automated certificate management.
- [ZITADEL](https://github.com/caos/zitadel) - Cloud-native Identity & Access Management solution providing a platform for secure authentication, authorization and identity management.
- [Authelia](https://www.authelia.com/) - The Single Sign-On Multi-Factor portal for web apps. ([Source Code](https://github.com/authelia/authelia)) `Apache-2.0``Go`
- [GLPI](https://www.glpi-project.org/) - Information Resource-Manager with an additional Administration Interface. ([Source Code](https://github.com/glpi-project/glpi))
- [OCS Inventory NG](https://ocsinventory-ng.org/) - Asset management and deployment solution for all devices in your IT Department. ([Source Code](https://github.com/OCSInventory-NG)) `GPL-2.0``PHP/Perl`
- [OPSI](http://www.opsi.org) - Hardware and software inventory, client management, deployment, and patching for Linux and Windows. ([Source Code](https://github.com/opsi-org/)) `GPL-3.0/AGPL-3.0``OVF/Python`
- [RackTables](http://racktables.org/) - Datacenter and server room asset management like document hardware assets, network addresses, space in racks, networks configuration. ([Source Code](https://github.com/RackTables/racktables), [Demo](https://www.racktables.org/demo.php)) `GPL-2.0``PHP`
- [Ralph](https://ralph.allegro.tech/) - Asset management, DCIM and CMDB system for large Data Centers as well as smaller LAN networks. ([Source Code](https://github.com/allegro/ralph), [Demo](https://github.com/allegro/ralph#live-demo)) `Apache-2.0``Python/Docker`
- [Flume](https://flume.apache.org/) - Distributed log collection and aggregation system.
- [GoAccess](http://goaccess.io/) - Real-time web log analyzer and interactive viewer that runs in a terminal or through the browser. ([Source Code](https://github.com/allinurl/goaccess)) `MIT``C`
- [Graylog](https://www.graylog.org/) - Pluggable Log and Event Analysis Server with Alerting options.
- [Hindsight](http://mozilla-services.github.io/hindsight/) - Stream processing system which may be used for log aggregation (Replaces Heka).
- [Kibana](https://www.elastic.co/products/kibana) - Visualize logs and time-stamped data.
- [Logstash](https://www.elastic.co/products/logstash) - Tool for managing events and logs.
- [Loki](https://grafana.com/oss/loki/) - horizontally-scalable, highly-available, multi-tenant log aggregation system inspired by Prometheus.
- [Claws Mail](http://www.claws-mail.org/) - Old school email client (and news reader), based on GTK+. ([Source Code](https://git.claws-mail.org/?p=claws.git;a=tree))
- [ImapSync](http://imapsync.lamiral.info/) – Simple IMAP migration tool for copying mailboxes to other servers. ([Source Code](https://github.com/imapsync/imapsync))
- [Sylpheed](http://sylpheed.sraoss.jp/en/) – Still developed predecessor to Claws Mail, lightweight mail client. ([Source Code](https://github.com/sylpheed-mail/sylpheed))
- [Thunderbird](https://www.thunderbird.net/) - Free email application that's easy to set up and customize. ([Source Code](https://hg.mozilla.org/comm-central/file))
- [Adagios](http://adagios.org/) - Web based Nagios interface for configuration and monitoring (replacement to the standard interface), and a REST interface. ([Source Code](https://github.com/opinkerfi/adagios)) `AGPL-3.0``Docker/Python`
- [Bloonix](https://bloonix-monitoring.org/) - Bloonix is a monitoring solution that helps businesses to ensure high availability and performance. ([Source Code](https://github.com/bloonix)) `GPL-3.0``Perl`
- [cadvisor](https://github.com/google/cadvisor) - Analyzes resource usage and performance characteristics of running containers ([Source Code](https://github.com/google/cadvisor)) `Apache-2.0``Go`
- [checkmk](https://checkmk.com/) - Comprehensive solution for monitoring of applications, servers, and networks. ([Source Code](https://github.com/tribe29/checkmk)) `Python/PHP`
- [EdMon](https://github.com/Edraens/EdMon) - A command-line monitoring application helping you to check that your hosts and services are available, with notifications support. `MIT``Java`
- [eZ Server Monitor](http://www.ezservermonitor.com) - A lightweight and simple dashboard monitor for Linux, available in Web and Bash application. ([Source Code](https://github.com/shevabam/ezservermonitor-web)) `GPL-3.0``PHP/Shell`
- [Icinga](https://www.icinga.com/) - Nagios fork that has since lapped nagios several times. Comes with the possibility of clustered monitoring. ([Source Code](https://github.com/Icinga/icinga2)) `GPL-2.0``C++`
- [LibreNMS](http://www.librenms.org) - Fully featured network monitoring system that provides a wealth of features and device support. ([Source Code](https://github.com/librenms/librenms)) `GPL-3.0``PHP`
- [Monit](http://mmonit.com/monit/#home) - Small utility for managing and monitoring Unix systems. ([Source Code](https://bitbucket.org/tildeslash/monit/src/master/)) `AGPL-3.0``C`
- [Naemon](http://www.naemon.org/) - Network monitoring tool based on the Nagios 4 core with performance enhancements and new features. ([Source Code](https://github.com/naemon/naemon-core)) `GPL-2.0``C`
- [Netdata](https://www.netdata.cloud/) - Distributed, real-time, performance and health monitoring for systems and applications. Runs on Linux, FreeBSD, and MacOS. ([Source Code](https://github.com/netdata/netdata)) `GPL-3.0``C`
- [NetXMS](https://www.netxms.org/) - Open Source network and infrastructure monitoring and management. ([Source Code](https://github.com/netxms/netxms)) `LGPL-3.0/GPL-3.0``Java/C++/C`
- [PHP Server Monitor](https://www.phpservermonitor.org/) - Open source tool to monitor your servers and websites. ([Source Code](https://github.com/phpservermon/phpservermon))
- [PhpSysInfo](https://phpsysinfo.github.io/phpsysinfo/) - A customizable PHP script that displays information about your system nicely. ([Source Code](https://github.com/phpsysinfo/phpsysinfo))
- [pyDash](https://k3oni.github.io/pydash/) - Small web-based monitoring dashboard for linux. ([Source Code](https://gitlab.com/k3oni/pydash))
- [Riemann](http://riemann.io/) - Flexible and fast events processor allowing complex events/metrics analysis. ([Source Code](https://github.com/riemann/riemann))
- [rtop](https://github.com/rapidloop/rtop) - an interactive, remote system monitoring tool based on SSH. ([Source Code](https://github.com/rapidloop/rtop))
- [Status](https://github.com/dani3l0/Status) - Simple and lightweight system monitoring tool for small homeservers with a pleasant web interface. ([Demo](https://status-ksk5.onrender.com/)) `MIT``Python`
- [Thruk](http://www.thruk.org/) - Multibackend monitoring web interface with support for Naemon, Nagios, Icinga and Shinken. ([Source Code](https://github.com/sni/Thruk))
- [Zabbix](http://www.zabbix.com/) - Enterprise-class software for monitoring of networks and applications. ([Source Code](https://git.zabbix.com/projects/ZBX/repos/zabbix/browse))
- [tcollector](http://opentsdb.net/docs/build/html/user_guide/utilities/tcollector.html) - System statistic collection daemon written in Python for OpenTSDB
- [Telegraf](https://github.com/influxdata/telegraf) - The plugin-driven server agent for collecting & reporting metrics.
- [Dashing](http://dashing.io/) - Ruby gem that allows for rapid statistical dashboard development. An all HTML5 approach allows for big screen displays in data centers or conference rooms.
- [Facette](http://facette.io) - Time series data visualization and graphing software written in Go.
- [Freeboard](https://github.com/Freeboard/freeboard) - A damn-sexy front-end real-time dashboard for the internet of things. Transforms raw JSON into delicious UI.
- [Ganglia](http://ganglia.sourceforge.net/) - High performance, scalable RRD based monitoring for grids and/or clusters of servers. Compatible with Graphite using a single collection process.
- [Grafana](http://grafana.org/) - A Graphite & InfluxDB Dashboard and Graph Editor.
- [RRDtool](http://oss.oetiker.ch/rrdtool/) - Industry standard, high performance data logging and graphing system for time series data.
- [OpenWISP](https://openwisp.org/) - Open Source Network Management System for OpenWRT based routers and access points. ([Demo](https://openwisp.org/demo.html), [Source Code](https://github.com/openwisp)) `GPL-3.0``Python`
- [phpIPAM](http://phpipam.net/) - Open source IP address management with PowerDNS integration. ([Source Code](https://github.com/phpipam/phpipam)) `GPL-3.0``PHP`
- [RANCID](http://www.shrubbery.net/rancid/) - Monitor network devices configuration and maintain history of changes. ([Source Code](https://github.com/haussli/rancid)) `BSD-3-Clause``Perl/Shell`
- [DadaMail](http://dadamailproject.com/) - Mailing List Manager, written in Perl.
- [Lewsnetter](https://github.com/bborn/lewsnetter) - E-mail marketing application (create and send e-mail newsletter via SES). Includes subscription management, delivery, bounce and complaint notification, templates, and some stats.
- [Remmina](http://www.remmina.org/wp/) - A Feature rich remote desktop application for linux and other unixes.
- [Tiger VNC](http://tigervnc.org/) - TigerVNC is a high-performance, platform-neutral implementation of VNC (Virtual Network Computing), a client/server application that allows users to launch and interact with graphical applications on remote machines.
- [X2go](http://wiki.x2go.org/doku.php) - X2Go is an open source remote desktop software for Linux that uses the NX technology protocol.
* [DD-WRT](https://dd-wrt.com/) - A Linux-based firmware for wireless routers and access points, originally designed for the Linksys WRT54G series. ([Source Code](https://svn.dd-wrt.com/)) `GPL-2.0``C`
* [OpenWrt](https://openwrt.org/) - A Linux-based router featuring Mesh networking, IPS via snort and AQM among many other features. ([Source Code](https://git.openwrt.org/openwrt/openwrt.git)) `GPL-2.0``C`
* [OPNsense](https://opnsense.org/) - An open source FreeBSD-based firewall and router with traffic shaping, load balancing, and virtual private network capabilities. ([Source Code](https://github.com/opnsense)) `BSD-2-Clause``C``PHP`
- [Consul](https://www.consul.io/) - Consul is a tool for service discovery, monitoring and configuration.
- [Doozerd](https://github.com/ha/doozerd) - Doozer is a highly-available, completely consistent store for small amounts of extremely important data.
- [etcd](https://github.com/coreos/etcd) - distributed K/V-Store, authenticating via SSL PKI and a REST HTTP Api for shared configuration and service discovery.
- [ZooKeeper](http://zookeeper.apache.org/) - ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services.
- [Podman](https://podman.io) - Daemonless container engine for developing, managing, and running OCI Containers on your Linux System. Containers can either be run as root or in rootless mode. Simply put: `alias docker=podman`. ([Source Code](https://github.com/containers/podman)) `Apache-2.0``Go`
- [systemd-nspawn](https://www.freedesktop.org/software/systemd/man/systemd-nspawn.html) - Lightweight, chroot-like, environment to run an OS or command directly under systemd. ([Source Code](https://github.com/systemd/systemd)) `GPL-2.0``C`
- [grml](https://grml.org) – bootable Debian Live CD with powerful CLI tools.
- [mitmproxy](http://mitmproxy.org/) - A Python tool used for intercepting, viewing and modifying network traffic. Invaluable in troubleshooting certain problems.
- [mtr](https://www.bitwizard.nl/mtr/) - Network utility that combines traceroute and ping.
- [perf-tools](https://github.com/brendangregg/perf-tools) - Performance analysis tools based on Linux perf_events (aka perf) and ftrace.
- [Sysdig](http://www.sysdig.org/) - Capture system state and activity from a running Linux instance, then save, filter and analyze.
- [Wireshark](https://www.wireshark.org/) - The world's foremost network protocol analyzer.
- [Archipel](http://archipelproject.org/) - XMPP based virtualization management platform.
- [ConVirt](http://www.convirture.com/products_opensource.php) - Provides the core functionality for centrally managing your KVM or Xen virtualized environment.
- [Ganeti](http://www.ganeti.org/) - Cluster virtual server management software tool built on top of KVM and Xen.
- [KVM](http://www.linux-kvm.org) - Linux kernel virtualization infrastructure.
- [OpenNebula](http://opennebula.org/) - Flexible enterprise cloud made simple.
- [PiVPN](https://www.pivpn.io/) - The simplest way to setup and manage a VPN, designed for Raspberry Pi. ([Source Code](https://github.com/pivpn/pivpn)) `MIT``Shell`
- [HAProxy](http://www.haproxy.org/) - Software based load Balancing, SSL offloading and performance optimization, compression, and general web routing.
- [Traefik](https://traefik.io/) - Traefik is a leading modern reverse proxy and load balancer.
- [Varnish](https://www.varnish-cache.org/) - HTTP based web application accelerator focusing on optimizing caching and compression.
- [Code as Craft](https://codeascraft.com/) - Etsy's Ops blog, lots of technical posts.
- [DevOpsGuys](http://blog.devopsguys.com/) - Devops consultants who blog about operations.
- [Rackspace Developers](https://developer.rackspace.com/blog/) - Slightly biased blog with lots of Devops Topics.
- [RoseHosting Blog](https://www.rosehosting.com/blog/) - Linux tutorials for installing and configuring various software through the Linux command line. Guides and introductions to different Linux technologies and applications. Tips and tricks you can do via the Linux command line and more.
- [Servers for Hackers](https://serversforhackers.com/) - Newsletter for programmers who find themselves needing to know their way around a server.
- [Web Operations Weekly](http://webopsweekly.com/) - A weekly newsletter on Web operations, infrastructure, performance, and tooling, from the browser down to the metal.
- [AlternativeTo](http://alternativeto.net) - Find alternatives to software you know and discover new software.
- [deb.sury.org](https://deb.sury.org/) - Repository with LAMP updated packages for Debian and Ubuntu.
- [ElRepo](http://elrepo.org/tiki/tiki-index.php) - Community Repo for Enterprise Linux (RHEL, CentOS, etc).
- [EPEL](https://fedoraproject.org/wiki/EPEL) - Repository for RHEL and compatibles (CentOS, Scientific Linux).
- [IUS](https://ius.io/) - Community project that provides RPM packages for newer versions of select software for Enterprise Linux distributions.
- [Remi](http://rpms.famillecollet.com/) - Repository with LAMP updated packages for RHEL/Centos/Fedora.
- [Software Collections](https://www.softwarecollections.org) - Community Release of [Red Hat Software Collections](https://access.redhat.com/documentation/en/red-hat-software-collections/). Provides updated packages of Ruby, Python, etc. for CentOS/Scientific Linux 6.x.
- [Awesome SysAdmin @ LibHunt](https://sysadmin.libhunt.com) - Your go-to SysAdmin Toolbox. Based on the list here.
- [Ops School](http://www.opsschool.org) - Comprehensive program that will help you learn to be an operations engineer.
- [Digital Ocean Tutorials](https://www.digitalocean.com/community/tutorials) - A surprisingly vast resource for getting the basics of certain applications, tools, or even systems administration topics.
