das_watchdog: command not found

Have You tried accessing the binary with the full path?

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/das_watchdog - from package: das-watchdog

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