rubber-info: 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/rubber-info - from package: rubber

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

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