radacct: 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/radacct - from package: radiusclient-ng-utils

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

On Debian possible default full paths are:

/usr/sbin/radacct - from package: libfreeradius-client-dev

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

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