bootstrap_firmware: 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/sbin/bootstrap_firmware - from package: firmware-tools

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

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