sdfapi: 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/sdfapi - from package: sdf

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

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