If you are trying to update the Catalog on one of the Mailbox DatabaseCopy you may see the following error
[PS] C:Windowssystem32>Update-MailboxDatabaseCopy “db01mbx1-10” -catalogonly
A source-side operation failed. Error Content indexing operation failed with the following message: The seeding operati on encountered an error while trying to contact the search service. Error: Microsoft Exchange Search Service may not be running on server MBX1-10. Specific RPC error message: Error 0x6d9 (There are no more endpoints available from the end point mapper) from cli_Dismount. [Database: DB01, Server: MBX1-10.TRADERS.COM] + CategoryInfo : InvalidOperation: (:) [Update-MailboxDatabaseCopy], CiSeederRpcOperationFailedException + FullyQualifiedErrorId : EEBEE7FA,Microsoft.Exchange.Management.SystemConfigurationTasks.UpdateDatabaseCopy
You may have to start Microsoft Exchange Serach Indexer service but it may not solve the issue so make sure it is running Microsoft Exchange RPC Client Access server
Once these services are started you will notice the same action after running the above cmdlet again
In Exchange 2010, passive database copies have a very low checkpoint depth, which is required for fast failover. In addition, the passive copy performs aggressive pre-reading of data to keep up with a 5-megabyte (MB) checkpoint depth. As a result of using a low checkpoint depth and performing these aggressive pre-read operations, IOPS for a passive database copy was equal to IOPS for an active copy in Exchange 2010.
In Exchange 2013, the system is able to provide fast failover while using a high checkpoint depth on the passive copy (100 MB). Because passive copies have 100-MB checkpoint depth, they’ve been de-tuned to no longer be so aggressive. As a result of increasing the checkpoint depth and de-tuning the aggressive pre-reads, IOPS for a passive copy is about 50 percent of the active copy IOPS in Exchange 2013.
Having a higher checkpoint depth on the passive copy also results in other changes. On failover in Exchange 2010, the database cache is flushed as the database is converted from a passive copy to an active copy.
In Exchange 2013, ESE logging was rewritten so that the cache is persisted through the transition from passive to active. Because ESE doesn’t need to flush the cache, you get fast failover.
One other change is background database maintenance (BDM). BDM is now throttled back from 5 MB per sec per copy to 1 MB per sec per copy.
As a result of these changes, Exchange 2013 provides a 50 percent reduction in IOPS over Exchange 2010.