snapperd: 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
/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/sbin/snapperd - from package: snapper

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