request help: Is Plugin shared memory shared across cluster

[sagivoulu]

Issue description

In many plugins I see the use of ngx.shared[] to store information (i.e. Circuit breaker counter, request limit counter etc...). Where does this information get stored? In the local memory of the api gateway? In the control plane etcd?

I am asking because some plugin use cases (request limiting, circuit breaker, authentication session and more) require this data to be stored in a shared memory store (i.e. Redis / memcash / etcd), so a cluster of apisix instances can access it.

B.T.W I know that some plugins have configuration options to specify a shared memory like redis, but I am not talking about these plugins.

[spacewander]

In the local memory of the api gateway.
See https://github.com/openresty/lua-nginx-module#ngxshareddict

[sagivoulu]

Thanks, that answers my question.