kadmin: 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/lib/heimdal/bin/kadmin - from package: heimdal-workstation
/usr/bin/kadmin - from package: krb5-workstation

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

On Debian possible default full paths are:

/usr/bin/kadmin - from package: krb5-user

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

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