swgen: 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/swgen - from package: siggen

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

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