cobbler: 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/cobbler - from package: cobbler

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

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