nnbatch: 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/nnbatch - from package: nn

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

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