To wrap this year, I’ve collected 50 UNIX / Linux sysadmin related tutorials that we’ve posted so far. This is lot of reading. Bookmark this article for your future reference and read it whenever you get free time. Disk to disk backup using dd command: dd is a powerful UNIX utility, which is used by the Linux kernel makefiles to make boot images. It can also be used to copy data. Ninite for Linux. Ubuntu. Gentoo. How-To: Cleaning up Gentoo to get more free disk space.