62 lines
1.8 KiB
Markdown
62 lines
1.8 KiB
Markdown
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# Theory of route
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## Why does this project exist?
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HTTP load balancing is harder than it needs to be. Existing projects assume
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there is a direct line-of-fire from the load balancer to the underlying services.
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This is NOT always true. Containerization has lead to a lot of hacks such as
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overlay networks to offer this direct line-of-fire so that the load balancer
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can make a direct TCP connection to the underlying services.
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Route exists to invert this problem.
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In most networks, it is true that it is a lot easier to guarantee the backends
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have a direct line-of-fire to the load balancer, not the other way around.
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Why not just make a connection to the load balancer and re-use it for HTTP
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traffic?
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Route allows you to simplify your network architecture by removing the
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requirement that all backend services need a direct TCP line-of-fire to the
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load balancer. Route allows you to host HTTP services behind NAT. Route
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allows you to throw out overlay networks and return to a simpler cluster layout.
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## How does route work?
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Route has several basic nouns, they are:
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- route
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- backend
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- balancer
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- agent
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They are inter-related like this:
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```graphviz
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digraph G {
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balancer -> agent
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agent -> balancer
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agent -> backend
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backend -> agent
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user -> balancer
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balancer -> user
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}
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```
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### route
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A route is a combination of HTTP domain and path (currently unsupported, so
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assume `/`). An example route would be `cloudsdale.cf/`. This maps to the
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location users get.
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### backend
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A backend is the underlying service being proxied to by route. An example backend
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is Apache, Nginx or anything else that serves compliant HTTP/1.1 traffic.
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### balancer
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A balancer is an instance of `cmd/routed` running on some server somewhere.
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Balancers accept both agent and HTTP connections, proxying requests from the HTTP
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connections to agent connections and back.
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