Redundant Virtual Router support in Isolated network with network mode set to Routed Dynamic

### Feature request

At the moment, the _Isolated network with Routed Dynamic network mode_ only supports running with a single virtual router. This means in the event of a host or VM failure, there will be a network outache of about 5 to 7 minutes. This virtual router is the default gateway of all VM's in this network, so the impact can mean downtime and loss of services (DHCP, DNS, networking).

### Solution

It would be great to have the same implementation as the "natted" virtual router type where keepalived is used between an active and passive virtual router in order to give redundancy.

Empieza rastreando la red Isolated con la implementación de Routed Dynamic virtual-router y comparándola con la implementación de natted virtual-router que usa keepalived. Se considera terminado cuando los virtual-router activos/pasivos proporcionen redundancia, de modo que un fallo del host o de la VM no interrumpa la puerta de enlace predeterminada, DHCP, DNS ni la red.

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