farpd: 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/farpd - from package: farpd

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

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