radclient: 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/radclient - from package: freeradius-utils

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

On Debian possible default full paths are:

/usr/bin/radclient - from package: freeradius-utils

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

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