roarctl: 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/roarctl - from package: roarclients

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

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