gsmartcontrol-root: 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/gsmartcontrol-root - from package: gsmartcontrol

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

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