On a fresh installation of Centos/Ubuntu you will sometimes find that the arrow keys don’t work whilst in vi- instead giving you something like:

Very frusting and usually has me grabbing nano instead. However, there are a couple of ways around this:

• apt-get install vim  (or use your favourite package manager) and instead use vim, which supports the arrow keys by default
• Or if you don’t want to install more software, set “:set nocompatible” and this should fix it also