ebtables: 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:

/sbin/ebtables - from package: ebtables

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

On Debian possible default full paths are:

/sbin/ebtables - from package: ebtables

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

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