I remember the behaviour of a mediator in the domain acts similarly to a participant node: both are connected to and relying on the sequencers plus underlying database/dlt.
In a HA setup, participant node is connected to more than one sequencers with connect_ha. And among them we always see the participant is always connected to one sequencer and the other one if the previous one is disconnected.
This is also applied to mediator? We don’t have explicit connection from mediator to sequencers. I wish to know if there is a primary sequencer which serves the mediator, OR all sequencers can forward to the mediator and all sequencers can respond to mediator’s message.
you are right that the mediators are also configured with multiple sequencers for fail-over, similar to participant nodes. The difference is that the mediator’s sequencer connections are configured as part of the domain bootstrapping:
bootstrap_domain: at the initial bootstrap of a domain, the mediators are configured to connect to the initial set of sequencers.
onboard_mediator: when adding another mediator to a domain, you can pass in multiple sequencer connections, which is similar to connect_ha.
The sequencers are operating in an active-active mode, therefore a mediator can connect to any sequencer that is available to read and submit messages.