restartd: 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/restartd - from package: restartd

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

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