upslug2: 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/sbin/upslug2 - from package: upslug2

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

Error in other languages:
upslug2: bevel nie gevind nie
upslug2: comandă negăsită
upslug2: comando não encontrado
upslug2: commande introuvable
upslug2: command not found
upslug2: käsku ei ole
upslug2: không tìm thấy lệnh
upslug2: komanda nerasta
upslug2: Kommando nicht gefunden.
upslug2: kommandot finns inte
upslug2: komut yok
upslug2: nie znaleziono polecenia
upslug2: níor aimsíodh an t-ordú
upslug2: no se encontró la orden
upslug2: no s'ha trobat l'ordre
upslug2: opdracht niet gevonden
upslug2: parancs nem található
upslug2: perintah tidak ditemukan
upslug2: príkaz nenájdený
upslug2: příkaz nenalezen
upslug2: команда не найдена
upslug2: командата не е открита
upslug2: 命令找不到
upslug2: コマンドが見つかりません