disnbi: 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/disnbi - from package: mknbi

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

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