kephra: 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/kephra - from package: kephra

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