Advantages Database Mirroring:
o Database Mirroring architecture is more robust and efficient than Database Log Shipping. It can be configured to replicate the changes synchronously to minimized data loss.
o It has automatic server failover and client failover mechanism.
o Configuration is simpler than log shipping and replication, and has built-in network encryption support (AES algorithm).
o Because propagation can be done asynchronously, it requires less bandwidth than synchronous method (e.g. host-based replication, clustering) and is not limited by geographical distance with current technology.
o Database mirroring supports full-text catalogs.
o Does not require special hardware (such as shared storage, heart-beat connection) and clusterware, thus potentially has lower infrastructure cost.
Disadvantages of Database Mirroring:
o Potential data lost is possible in asynchronous operation mode. RTO will vary and depend on several factors, such as propagation interval time and bandwidth speed.
o Mirror server/database is not available for user operation.
o It only works at database level and not at server level. It only propagates changes at database level, no server level objects, such as logins and fixed server role membership, can be propagated.
o Automatic server failover may not be suitable for application using multiple databases.