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When I am restoring Log Backups in Mirror Database is taking 30 mins. so that time how do we restore the principle database transactions to the mirror database. because the principle database is Large OLTP Database.
30 minutes is not a problem. If you want you can make and restore additional log backups to the mirror server, as long as they are restored in sequence. Make sure to specify WITH NORECOVERY on each restore, and once the last backup is restored you use ALTER DATABASE ... SET PARTNER on the mirror, then the principal. That will finalize the configuration and start mirror synchronization.