ipip: 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/ipip - from package: ipip

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

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