sntp: 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/sntp - from package: ntp

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

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