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Securing Linux systems  |    A 5 day   hands on   training course

Securing Linux systems training course description

This course teaches you everything you need to know to build a safe Linux environment. The first section handles cryptography and authentication with certificates, openssl, mod_ssl, DNSSEC and filesystem encryption. Then Host security and hardening is covered with intrusion detection, and also user management and authentication. Filesystem Access control is then covered. Finally network security is covered with network hardening, packet filtering and VPNs.

What will you learn
  • Secure Linux accounts.
  • Secure Linux file systems.
  • Secure Linux access through the network.
Securing Linux systems training course details

Securing Linux systems training course contents

  • Cryptography
  • Certificates and Public Key Infrastructures
  • X.509 certificates, lifecycle, fields and certificate extensions. Trust chains and PKI. openssl. Public and private keys. Certification authority. Manage server and client certificates. Revoke certificates and CAs.

  • Encryption, signing and authentication
  • SSL, TLS, protocol versions. Transport layer security threats, e.g. MITM. Apache HTTPD with mod_ssl for HTTPS service, including SNI and HSTS. HTTPD with mod_ssl to authenticate users using certificates. HTTPD with mod_ssl to provide OCSP stapling. Use OpenSSL for SSL/TLS client and server tests.

  • Encrypted File Systems
  • Block device and file system encryption. dm-crypt with LUKS to encrypt block devices. eCryptfs to encrypt file systems, including home directories and, PAM integration, plain dm-crypt and EncFS.

  • DNS and cryptography
  • DNSSEC and DANE. BIND as an authoritative name server serving DNSSEC secured zones. BIND as an recursive name server that performs DNSSEC validation, KSK, ZSK, Key Tag, Key generation, key storage, key management and key rollover, Maintenance and resigning of zones, Use DANE. TSIG.

  • Host Security
  • Host Hardening
  • BIOS and boot loader (GRUB 2) security. Disable useless software and services, sysctl for security related kernel configuration, particularly ASLR, Exec-Shield and IP / ICMP configuration, Exec-Shield and IP / ICMP configuration, Limit resource usage. Work with chroot environments, Security advantages of virtualization.

  • Host Intrusion Detection
  • The Linux Audit system, chkrootkit, rkhunter, including updates, Linux Malware Detect, Automate host scans using cron, AIDE, including rule management, OpenSCAP.

  • User Management and Authentication
  • NSS and PAM, Enforce password policies. Lock accounts automatically after failed login attempts, SSSD, Configure NSS and PAM for use with SSSD, SSSD authentication against Active Directory, IPA, LDAP, Kerberos and local domains, Kerberos and local domains, Kerberos tickets.

  • FreeIPA Installation and Samba Integration
  • FreeIPA, architecture and components. Install and manage a FreeIPA server and domain, Active Directory replication and Kerberos cross-realm trusts, sudo, autofs, SSH and SELinux integration in FreeIPA.

  • Access Control
  • Discretionary Access Control
  • File ownership and permissions, SUID, SGID. Access control lists, extended attributes and attribute classes.

  • Mandatory Access Control
  • TE, RBAC, MAC, DAC. SELinux, AppArmor and Smack.

  • etwork File Systems
  • NFSv4 security issues and improvements, NFSv4 server and clients, NFSv4 authentication mechanisms (LIPKEY, SPKM, Kerberos), NFSv4 pseudo file system, NFSv4 ACLs. CIFS clients, CIFS Unix Extensions, CIFS security modes (NTLM, Kerberos), mapping and handling of CIFS ACLs and SIDs in a Linux system.

  • Network Security
  • Network Hardening
  • FreeRADIUS, nmap, scan methods. Wireshark, filters and statistics. Rogue router advertisements and DHCP messages.

  • Network Intrusion Detection
  • ntop, Cacti, bandwidth usage monitoring, Snort, rule management, OpenVAS, NASL.

  • Packet Filtering
  • Firewall architectures, DMZ, netfilter, iptables and ip6tables, standard modules, tests and targets. IPv4 and IPv6 packet filtering. Connection tracking, NAT. IP sets and netfilter rules, nftables and nft. ebtables. conntrackd

  • Virtual Private Networks
  • OpenVPN server and clients for both bridged and routed VPN networks. IPsec server and clients for routed VPN networks using IPsec-Tools / racoon. L2TP.

Learning path



Based on customer ratings

D. M.- Paradigm

"I’ve found it very useful and the course was very well put together and delivered."

R. B. - Serco DNS

"Course was tailored to our requirements. Very flexible."

Training approach

This structured course uses Instructor Led Training to provide the best possible learning experience. Small class sizes ensure students benefit from our engaging and interactive style of teaching with delegates encouraged to ask questions throughout the course. Quizzes follow each major section allowing checking of learning. Hands on sessions are used throughout to allow delegates to consolidate their new skills.