kdb5_util: 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/sbin/kdb5_util - from package: krb5-server

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

On Debian possible default full paths are:

/usr/sbin/kdb5_util - from package: krb5-kdc

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

Error in other languages:
kdb5_util: bevel nie gevind nie
kdb5_util: comandă negăsită
kdb5_util: comando não encontrado
kdb5_util: commande introuvable
kdb5_util: command not found
kdb5_util: käsku ei ole
kdb5_util: không tìm thấy lệnh
kdb5_util: komanda nerasta
kdb5_util: Kommando nicht gefunden.
kdb5_util: kommandot finns inte
kdb5_util: komut yok
kdb5_util: nie znaleziono polecenia
kdb5_util: níor aimsíodh an t-ordú
kdb5_util: no se encontró la orden
kdb5_util: no s'ha trobat l'ordre
kdb5_util: opdracht niet gevonden
kdb5_util: parancs nem található
kdb5_util: perintah tidak ditemukan
kdb5_util: príkaz nenájdený
kdb5_util: příkaz nenalezen
kdb5_util: команда не найдена
kdb5_util: командата не е открита
kdb5_util: 命令找不到
kdb5_util: コマンドが見つかりません