ekey-rekey: 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/ekey-rekey - from package: ekeyd

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