ebtables-save: 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-save - from package: ebtables

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

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