Managing Transit Traffic with the Overload Bit

If a router lacks the resources to maintain a complete link state database, routing packets to it could result in a blackhole or routing loop. The overload bit prevents this undesirable behavior by indicating to the other routers that the afflicted router should not be used as a transit router. Packets destined for directly attached routes can still be routed to a router with the overload bit set, but all other routing paths reconverge around it.