try_tcp_on_error

Since: Version 2025.03.19-1d3f1f67

The functionality described in this section requires version 2025.03.19-1d3f1f67 of KumoMTA, or a more recent version.

Boolean. When true, if a query against a name server's UDP connection errors, the resolver immediately retries the same query over that name server's TCP connection (if one is configured) before consulting other name servers. Defaults to false.