ShellEnhancement

sort -u /root/.bash_history -o /root/.bash_history

Expand memory of you .bash_history

Expand the "memory of your .bash_history to 2000 lines adding this on your .bashrc:

export HISTFILESIZE=2000
export HISTSIZE=2000

Easy search using arrows

Create a .inputrc, or edit your /etc/inputrc, with :

"\e[A": history-search-backward
"\e[B": history-search-forward

Next logon you'll be able to search command by start to write them and use up/down arrows.

"\e[1;5A": history-search-backward
"\e[1;5B": history-search-forward

Will allow you to use ctrl+up/down arrows (and your up/down arrows will work as usual).