radmin: 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/radmin - from package: freeradius

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

On Debian possible default full paths are:

/usr/sbin/radmin - from package: freeradius
/usr/lib/debug/usr/sbin/radmin - from package: freeradius-dbg

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

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