openstack: 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/openstack - from package: python-openstackclient

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

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