The commands reside under /sbin which isn't in the $PATH environment variable of regular users (because many of those commands don't work when run by a non-root user). Try
instead, or if you run su
to become root, use
instead, it takes root's $PATH variable into use and you don't need to type /sbin/ in front of the commands.
Shortly: all the commands are there, and even in the same place where you've used to, but you don't have /sbin/ included in the environment variable that tells your shell which paths to look for a command if it's full path is not given.