ale: 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/bin/ale - from package: ale

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

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