snake-machine: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/sbin/snake-machine - from package: snake

You may install the required package with command yum install {package}

Error in other languages:
snake-machine: bevel nie gevind nie
snake-machine: comandă negăsită
snake-machine: comando não encontrado
snake-machine: commande introuvable
snake-machine: command not found
snake-machine: käsku ei ole
snake-machine: không tìm thấy lệnh
snake-machine: komanda nerasta
snake-machine: Kommando nicht gefunden.
snake-machine: kommandot finns inte
snake-machine: komut yok
snake-machine: nie znaleziono polecenia
snake-machine: níor aimsíodh an t-ordú
snake-machine: no se encontró la orden
snake-machine: no s'ha trobat l'ordre
snake-machine: opdracht niet gevonden
snake-machine: parancs nem található
snake-machine: perintah tidak ditemukan
snake-machine: príkaz nenájdený
snake-machine: příkaz nenalezen
snake-machine: команда не найдена
snake-machine: командата не е открита
snake-machine: 命令找不到
snake-machine: コマンドが見つかりません