keystone: 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 Debian possible default full paths are:

/usr/bin/keystone - from package: python-keystoneclient

You may install the required package with command apt-get install {package}

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