cassiopeeknife: 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/cassiopeeknife - from package: cassiopee

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

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