idevice_id: 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 CentOS possible default full paths are:

/usr/bin/idevice_id - from package: libimobiledevice

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/idevice_id - from package: libimobiledevice-utils

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

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