The Log Reader Agent creates a dynamic linked server for the listener to verify the metadata when you configure a transactional publication on an Always On availability group (AG). This dynamic linked server is temporary and dropped after the verification. When the AG is deployed with replicas in different subnets, this dynamic linked server connection might time out as it tries to connect serially. After applying the fix, if the Log Reader Agent is configured to use the MultiSubnetFailover parameter as 1, the dynamic linked server is also created with the MultiSubnetFailover parameter as 1, which allows connection to occur in parallel.
