eulb-delete-lb-listeners: 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/eulb-delete-lb-listeners - from package: euca2ools

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

On Debian possible default full paths are:

/usr/bin/eulb-delete-lb-listeners - from package: euca2ools

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

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