Related to https://github.com/matrix-org/synapse/pull/15491
This doesn't hurt to be done early on, while still on Synapse v1.83.0.
We'll be able to remove the `worker_replication_*` settings later,
when Synapse v1.84.0 gets released and starts making use of the new
`main` instance in the instance map instead of looking at the
`worker_replication_*` settings.
# matrix_synapse_instance_map holds the instance map used for mapping worker names (for certain generic workers only!) to where they live (host, port which handles replication traffic).
# This is populated automatically based on `matrix_synapse_workers_enabled_list` during runtime, so you're not required to tweak it manually.
matrix_synapse_instance_map:{}
# matrix_synapse_instance_map holds the instance map used for mapping worker names (for the main process and certain generic workers only!) to where they live (host, port which handles replication traffic).
# This map starts off being populated with the Synapse main (master) process,
# but will be populated with workers automatically during runtime, based on `matrix_synapse_workers_enabled_list`.