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README.md

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 A collection of awesome security hardening guides, best practices, tools and other resources.
 This is work in progress: please contribute by forking, editing and sending pull requests. You may also send suggestions on Twitter to [@decalage2](https://twitter.com/decalage2), or use https://www.decalage.info/contact
 
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+# Table of Contents
+- [Security Hardening Guides and Best Practices](#security-hardening-guides-and-best-practices)
+  - [Hardening Guide Collections](#hardening-guide-collections)
+  - [GNU/Linux](#gnulinux)
+    - [Red Hat Enterprise Linux - RHEL](#red-hat-enterprise-linux---rhel)
+    - [SUSE](#suse)
+    - [Ubuntu](#ubuntu)
+  - [Windows](#windows)
+  - [macOS](#macos)
+  - [Network Devices](#network-devices)
+    - [Switches](#switches)
+    - [Routers](#routers)
+  - [Virtualization - VMware](#virtualization---vmware)
+  - [Services](#services)
+    - [SSH](#ssh)
+    - [TLS/SSL](#tlsssl)
+    - [Web Servers](#web-servers)
+      - [Apache HTTP Server](#apache-http-server)
+      - [Apache Tomcat](#apache-tomcat)
+      - [Eclipse Jetty](#eclipse-jetty)
+      - [Microsoft IIS](#microsoft-iis)
+    - [Mail Servers](#mail-servers)
+    - [FTP Servers](#ftp-servers)
+    - [Database Servers](#database-servers)
+    - [LDAP](#ldap)
+    - [DNS](#dns)
+    - [NTP](#ntp)
+    - [CUPS](#cups)
+  - [Authentication - Passwords](#authentication---passwords)
+  - [Hardware - BIOS - UEFI](#hardware---bios---uefi)
+  - [Cloud](#cloud)
+- [Tools](#tools)
+  - [Tools to check security hardening](#tools-to-check-security-hardening)
+    - [GNU/Linux](#gnulinux-1)
+    - [Network Devices](#network-devices-1)
+    - [TLS/SSL](#tlsssl-1)
+  - [Tools to apply security hardening](#tools-to-apply-security-hardening)
+    - [GNU/Linux](#gnulinux-2)
+    - [Windows](#windows-1)
+- [Books](#books)
+
+
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 # Security Hardening Guides and Best Practices