Replication does not continue after a log shipping failover. If a failover occurs, replication agents do not connect to the secondary, so transactions are not replicated to Subscribers. If a fallback to the primary occurs, replication resumes. All transactions that log shipping COPIES from the secondary back to the primary are replicated to Subscribers.

For transactional replication, the behaviour of log shipping depends on the sync with a backup OPTION. This option can be set on the publication database and distribution database; in log shipping for the Publisher, only the setting on the publication database is relevant.

Setting this option on the publication database ensures that transactions are not delivered to the distribution database until they are BACKED up at the publication database. The last publication database backup can then be restored at the secondary server without any POSSIBILITY of the distribution database having transactions that the restored publication database does not have. This option guarantees that if the Publisher fails over to a secondary server, consistency is maintained between the Publisher, Distributor, and Subscribers. Latency and throughput are affected because transactions cannot be delivered to the distribution database until they have been backed up at the Publisher.