ipconfig: 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/lib/klibc/bin/ipconfig - from package: klibc-utils

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

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