srp_daemon: 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/srp_daemon - from package: srptools

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

On Debian possible default full paths are:

/usr/sbin/srp_daemon - from package: srptools

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

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