fai-do-scripts: 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

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/fai-do-scripts - from package: fai-client

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