In a federation, currently only subscribers keep track of external and internal subscriptions, publisher instances only publish to remote instance (router to router) because of this when a remote instance gets connected, a remote publisher detects a federated instance as connected and start sending messages but the remote instance might not have subscribers up and ready to receive the published messages.
This was fine earlier when we didn't have federation cache enabled, however with cache, when a federated instance reconnects a publisher instance starts replaying cached message right after the subscriber instance starts up but the agents (actual subscribers) might not be up and running and hence could lead to loss of cache replayed messages.
In a federation, currently only subscribers keep track of external and internal subscriptions, publisher instances only publish to remote instance (router to router) because of this when a remote instance gets connected, a remote publisher detects a federated instance as connected and start sending messages but the remote instance might not have subscribers up and ready to receive the published messages.
This was fine earlier when we didn't have federation cache enabled, however with cache, when a federated instance reconnects a publisher instance starts replaying cached message right after the subscriber instance starts up but the agents (actual subscribers) might not be up and running and hence could lead to loss of cache replayed messages.