dh_di_numbers: 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/dh_di_numbers - from package: dh-di

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

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