mpt-status: 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/sbin/mpt-status - from package: mpt-status

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

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