scala: 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/scala - from package: scala

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

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