nova-api: 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/nova-api - from package: nova-api

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

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