roota: 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/roota - from package: libroot-static

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

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