Subnets are assigned a routing table, and in the case of a Public subnet, the default route of this table is pointed at the Internet Gateway. Should the NAT instance go down, nothing in that subnet can speak to the outside world; the default-route becomes a black-hole. NAME. VM::EC2::VPC::Route — An entry in a VPC routing table. I’m loving the aws-vpc backend, but currently you can’t run more than one cluster under the same route table, as they risk overwriting each other’s routes.
Each subnet in your VPC must be associated with a route table. Typically, a router performs a Layer 3 route table lookup and Layer 3 forwarding when the destination MAC in the Ethernet frame matches its own MAC address. Figure 3-4 shows an example of where the delay can be used to avoid black hole traffic when a Cisco Nexus 5000 Platform switch is configured for Layer 3 with vPC. ‘association.main’ – Indicates whether the route table is the main route table for the VPC. The blackhole state indicates that the route’s target isn’t available (for example, the specified gateway isn’t attached to the VPC, the specified NAT instance has been terminated, and so on).
A route table specifies how packets are forwarded between the sub-nets within your VPC, the Internet, and your VPN connection so we need to create routing table Nat_Testing_Routing_public for the same. Status is showing Black Hole because my NAT instances are in stop state. Each subnet in your VPC must be associated with a route table; the table controls the routing for the subnet. A subnet can only be associated with one route table at a time, but you can associate multiple subnets with the same route table. ID of a VPC peering connection specified by a route in the table. route.origin. which operation created a route in the table. route.state. whether a route in the table has state active or blackhole. tag-key. key of a tag assigned to the route table.
I added a new route in the main routing table for this, pointing to the same vgw as the others. When I know look at the routes, I see that the original 3 routes are propagated, but the 4th new one is not. How can I close a big hole in a mesh? The public routing table will have a default route that goes to the Internet gateway. Note that the route status will turn to Black Hole if the NAT instance is offline. With working BGP, you will also see some additional dynamic routes to AWS VPC in your route table as below. A – active, D – dynamic, C – connect, S – static, r – rip, b – bgp, o – ospf, m – mme, B – blackhole, U – unreachable, P – prohibit DST-ADDRESS PREF-SRC GATEWAY DISTANCE 0 A S 0.