auth-relaytest: 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 Debian possible default full paths are:

/usr/bin/auth-relaytest - from package: dsbltesters

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