Canton error: "domain with the given alias has already been added"

When invoking LocalParticipantReference.domains.connect, we get an error “The domain with the given alias has already been added”. We’re using Canton 0.27.0.

Thanks for reaching out!

This error means that the domain alias you are using is already in use:
https://www.canton.io/docs/stable/user-manual/usermanual/error_codes.html#CN10054

It typically means that you have connected to a domain, persisted the domain registration to your db (which happens automatically as part of connect) and now you are calling connect again.

You can avoid the error by calling reconnect instead of connect.

Since Canton 1.0.0 (still to be released), connect (and similar commands) have been changed to be idempotent. So you can also call connect again, as you do right now.