dbd: 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/dbd - from package: jday

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

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