crunch: 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/crunch - from package: crunch

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

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