nova-dhcpbridge: 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 Debian possible default full paths are:

/usr/bin/nova-dhcpbridge - from package: nova-network

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

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