fiu-ctrl: 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/fiu-ctrl - from package: fiu-utils

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

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