Hi Vladimir, As you said, today, it's possible to use a LB in front of multiple instances (using nginx, ELB, ...). I think it's pretty easy to setup and at "infrastructure" level.
As it's possible to plug the HTTP5 client in Iceberg REST client, I think it's possible to inject PoolingHttpClientConnectionManager with multiple routes/host. I'm still prefer to define this at "infra" level (to decouple endpoints definition from the pure client). Regards JB On Mon, Dec 9, 2024 at 5:10 PM Vladimir Ozerov <voze...@querifylabs.com> wrote: > > Hi, > > Catalog is a critical part of Iceberg infrastructure and may require highly > available setup. In similar services (e.g., HMS, etc) this is often done as > follows: > > Start several service instances > Decide which one is coordinator via etcd, Zookeper, Ratis, etc > Expose HA endpoint to a client: multiple endpoints OR a single endpoint via > proxy > > Currently, there is no way to expose multiple endpoints to a REST server. > This may work in some cases if you hide multiple REST server instances behind > a proxy/balancer. But this proxy requires own HA setup, which complicates the > overall deployment. > > I'd like to ask the community whether we can extend REST specification with > multiple endpoints to support HA REST catalog without proxies. This extension > could contain two essential parts: > > How to provide multiple endpoints to RESTSessionCatalog. This could be > encoded into URL or as additional property > Some additional headers and/or error codes to allow a REST server instance > communicate peer endpoints and the current coordinator > > A very rough example how this can work in practice. Configuration: > > mycatalog.endpoint=https://host1 > mycatalog.endpoints=https://host1,https://host2,https://host3 > > REST server response headers with additional endpoints: > > X-HA-Coordinator: https://host2 > X-HA-Endpoints: https://host1,https://host2,https://host3 > > WDYT? > > Regards, > Vladimir
