ideviceprovision: 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/bin/ideviceprovision - from package: libimobiledevice-utils

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