pynast: 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/pynast - from package: pynast

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

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