dr_unsort: 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/dr_unsort - from package: draai

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

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