User-defined routing
By default, Azure automatically creates system routes and assigns them to the different subnets within a VNet. These routes can't be removed but can be overridden by custom routes known as User-Defined Routes (UDRs). These routes have a next hop setting that points to the next interface from a routing perspective so that traffic can be sent to the correct destination.
There are three main next hop types for system routes:
- VNet: This routes traffic between address ranges within the address space of a VNet.
- Internet: This routes traffic specified by the address prefix to the internet; the default route is
0.0.0.0/0, which means anything by default is routed to the internet. - None: Traffic routed to a next hop type as none is dropped.
UDRs create a route table if you want to create custom routes. When working with UDRs, it is important to note that they support the preceding routing types as well as the following:
- VNet gateway...