Previously, instances connected to tenant networks gained outside connectivity by going through an SNAT by the L3 agent hosting that network's virtual router. With this release, the ability to disable SNAT/PAT on virtual servers is added ensuring that an instance in a tenant network subnet will retain its IP address as it passes through external networks. For example, if 10.0.0.1 is an instance in the 10.0.0.0/8 tenant network, R1, a virtual router that connects the 10.0.0.0/8 subnet to the 20.0.0.0/8 public provider networks, then you can use the 'neutron router-gateway-set --disable-snat R1 public' command and any traffic from 10.0.0.1, which is forwarded out to the provider network will retain its actual source IP address of 10.0.0.1. This can be a flexible and useful method to connect instances directly to a provider network, while retaining it in a tenant network.