The Debian Administrator’s Handbook is a professional book that "covers all the topics that a competent Linux administrator should master, from the installation and the update of the system, up to the creation of packages and the compilation of the kernel, but also monitoring, backup and migration, without forgetting advanced topics like SELinux setup to secure services, automated installations, or virtualization with Xen, KVM or LXC".
Ubuntu is a Debian-based Linux distro, thus making a solid amount of informations presented in the book usable under Ubuntu.
After 5 months of work, The Debian Administrator’s Handbook is now available for download both as a printed payed version (€44.90) and free ebook (EPUB, MOBI, PDF).
Furthermore, the book is available online for users who want only to read various chapters, searching a particular item, comparing various methods, etc without the need to buy or download the 20+MB ebook.
Adopting as a motto "Debian Squeeze from Discovery to Mastery", The Debian Administrator’s Handbook takes the user from the very basics (why free software and foundations, what is Debian?, etc) to key features (dependencies, package conflicts, installation and upgrade, package removal, maneuvering packages via dpkg, apt-get commands, synaptic, network configuration, setting hostnames, GRUB configuration, etc) and more complex actions (compiling a kernel, backing up with rsync, virtual private network, RAID and LVM, virtualization, firewall, dealing with a compromised machine, creating a .deb package, etc).
The Debian Administrator’s Handbook can be bought from http://www.lulu.com/commerce/index.php?fBuyContent=12842768 , downloaded for free (EPUB, MOBI, PDF) from http://debian-handbook.info/get/now/ , and read online on http://debian-handbook.info/browse/stable/
As an alternative download method, the ebook is available via torrent