bucardo_ctl: 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/sbin/bucardo_ctl - from package: bucardo

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