nova-compute: command not found

Have You tried accessing the binary with the full path?

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/nova-compute - from package: nova-compute

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