scrub: 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 CentOS possible default full paths are:

/usr/bin/scrub - from package: scrub

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/scrub - from package: scrub

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

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