runvdr: 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/sbin/runvdr - from package: vdr

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

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