drbl-nfs-exports: 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/share/drbl/sbin/drbl-nfs-exports - from package: drbl

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

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