tmda-rfilter: command not found

Have You tried accessing the binary with the full path?

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/tmda-rfilter - from package: tmda

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