efa: 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/efa - from package: libtravel-routing-de-vrr-perl

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