netload: 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/netload - from package: netdiag

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

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