This book is based on Red Hat(R) Enterprise Linux 6 (RHEL 6) and it covers three main objectives: a resource for administrators who intend to take the new Red Hat Certified System Administrator (EX200) and the Red Hat Certified Engineer (EX300) exams and pass them; a quick and valuable on-the-job resource; and an easy-to-understand guide to novice and non-RHEL administrators. This book is divided into RHCSA and RHCE sections based on the exam objectives. It includes 21 chapters in total and is structured to facilitate readers to grasp concepts, understand implementation procedures, and learn commands, tools, configuration files, log files, and service daemons involved. The RHCSA Section (chapters 1 to 13) covers all the topics required to prepare for the RHCSA exam. Information presented includes general Linux concepts, basic commands, archiving, compression, file manipulation, file security, text editors, shell features, awk programming, hardware management, local installation, package administration, virtualization, network installation, automated installation, boot procedures, kernel management, user & group administration, disk partitioning, file system & swap management, basic firewall, SELinux, TCP Wrappers, basic networking, network interfaces, and DNS, DHCP, and LDAP client configuration. The RHCE Section (chapters 14 to 21) covers all the topics required to prepare for the RHCE exam. Information presented includes automating with scripting, building an rpm package, resource utilization reporting, network logging, advanced firewall, iSCSI, DNS server, Kerberos, routing, Internet services, kernel parameters, NTP client, email, NFS, Samba, FTP, Apache web server, and secure shell server. This book covers ALL official exam objectives and includes 100+ exercises, 550+ exam review questions, 70+ practice labs, and 2 sample exams. This book is not a replacement for RHCT(R)/RHCE(R) training courses offered by Red Hat, Inc., but may be used to prepare for both the exams. The information contained in this book is not endorsed by Red Hat, Inc. Good Luck with the book...