> For the complete documentation index, see [llms.txt](https://yeasy.gitbook.io/openstack_code_neutron/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://yeasy.gitbook.io/openstack_code_neutron/neutron/extensions/l3_ext_gw_modepy.md).

# l3\_ext\_gw\_mode.py

L3\_ext\_gw\_mode扩展类，继承自extensions.ExtensionDescriptor，为路由器提供外部网关支持。