drs_tool: 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/drs_tool - from package: drslib

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

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