keydctl: 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/bin/keydctl - from package: onak

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