On 7/27/21 10:54, Vimal wrote:
(Unsure if this is the right forum to ask this question, but here goes:)
From what I understand, IP Anycast can be used to steer traffic into a server that's close to the client.
I am curious if anyone here has/encountered a setup where they use anycast IP on their gateways... to have a predictable egress IP for their traffic, regardless of where they are located?
Stateless outbound load-balancing setups exist. Example you have two or more nat44 / nat64 / cgnat boxes behind a common ecmp path with the same destination IP(s). this is normally so that you have more boxes that accumulate state rather than being bound to a single one.
For example, a search engine crawler could in principle have the same IP advertised all over the world, but it looks like they don't... I wonder why?
So this is a somewhat different problem... There's no assurance that when you initiate a connection that the return path will return to the same instance of your anycast announcement when the server on the other side replies. Effectively the initiating party needs a unicast address or you need some out of band path to get an errant packet back to the correct host.
-- Vimal