sngetd: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH

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/sbin/sngetd - from package: sn

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