stund: 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/stund - from package: libnice

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

On Debian possible default full paths are:

/usr/sbin/stund - from package: stun

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

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