RFC Title
To be Reviewed By:
Authors: Alberto Bustamante
Status: Draft | Discussion | Active | Dropped | Superseded
Superseded by: N/A
Related: N/A
Problem
There is a problem with Geode WAN replication when GW receivers are configured with the same hostname-for-senders and port on all servers. The reason for such a setup is deploying Geode cluster on a Kubernetes cluster where all GW receivers are reachable from the outside world on the same VIP and port. Other kinds of configuration (different hostname and/or different port for each GW receiver) are not cheap from OAM and resources perspective in cloud native environments and also limit some important use-cases (like scaling).
Currently, it is possible to set GW receivers as described, but there are some problems derived from this configuration that must be solved prior to state that this configuration is supported by Geode.
Gw sender failover
The problem experienced is that shutting down one server is stopping replication to this cluster until the server is up again. This is because Geode incorrectly assumes there are no more alive servers when just one of them is down, because since they share hostname-for-senders and port, they are treated as one same server.
Gw sender pings not reaching gw receivers
Gw sender use internally a client pool which sends ping messages to the gw receiver it is connected to. In the receivers, ClientHealthMonitor thread is in charge of handle these ping messages. If no one is received from a given sender, it is considered down and the connection is closed. When configuring all gw receivers with same host and port, ping messages are not reaching all the receivers, so connections are closed.What is this proposal solving? Why does the problem matter? How does the problem affect the user?
Anti-Goals
What is outside the scope of what the proposal is trying to solve?
Solution
Gw sender failover
on going
Gw sender pings not reaching gw receivers
Describe your solution and how it’s going to solve the problem. This is likely the largest section of your proposal and might even include some high-level diagrams if you are proposing code changes. While all important aspects need to be covered, also keep in mind that shorter documents are more likely to be read.on going
Changes and Additions to Public Interfaces
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