DAG

Exchange 2013 Preferred Architecture

Here’s a cut-to-the-chase summary of The Preferred Architecture blog by Ross Smith IV, you will find a link for the original article at the end of this blog.

Here’s the summary (with el touch beta3y):

  • Simplicity, Simplicity, Simplicity.
  • For each exchange service (OWA, SMTP,…) Use one name that balances the connections between the 2 datacenters (If you have 2 Datacenter with “fast” network connection).
  • Each datacenter is a separate AD site.
  • All Exchange servers are multi-role servers (Each Server have Mailbox and CAS roles).
  • All Exchange servers are Physical servers!!!
  • 2 Disks in a RAID 1 to host the OS, Exchange binaries, protocol/client logs, and transport database.
  • JBOD SAS 7.2K disks with large capacity for Databases files and logs.
  • AutoReseed is enabled, and at least 1 disk is reserved for it.
  • DAG is stretched across the 2 Datacenters, and active copies distributed equally across all servers in the DAG.
  • Each Datacenter have the same number of Servers in the DAG.
  • The DAG have even numbers of servers, and a witness server is used for for quorum arbitration.
  • DAG’s witness server is placed in a third reliable Datacenter.
  • Use a single network card that will carry both MAPI and Replication traffic (Assuming you network infrastructure can provides 10 Gb end-to-end).
  • Each database has four copies, with two copies in each datacenter
  • ReplayLagTime is 7 days for the lagged database copy (Set-MailboxDatabaseCopy -Identity DatabaseName\MailboxServerName -ReplayLagTime 7.0:0:0)
  • Backup, Backup, backup.

References:

The Preferred Architecture

Configure AutoReseed for a database availability group

Ticket#6: While adding a server to a DAG, Operation fails with Error 0x6f7

In Exchange 2010, While you add a server to a Database Availability Group (DAG), you may receive the below error:

Error:
A server-side database availability group administrative operation failed. Error: The operation failed with message: Error 0x6f7 (The stub received bad date) from cli_RpccCreateCluster

Error 0x6f7 (The stub received bad data) from cli_RpccCreateCluster

Warning:
The operation wasn’t successful because an error was encountered. You may find more details in log file “C:\ExchangeSetupLogs\DagTasks\dagtask_xxxxxxx_add-databaseavailabilitygroupserver.log”

Exchange Management Shell command attempted:
Add-DatabaseAvailabilityGroupServer -Identity ‘DAG01’ -MailboxServer ‘SERVER NAME’

DAG Error 0x6f7

and you can check the mentioned log file (….add-databaseavailabilitygroupserver.log) for more details.
Cause:

You know that when you prepare the server to be a member in a DAG, you configure 2 network cards on that server, one for connectivity to other Exchange servers and other services (MAPI NIC), and the other one for Replication (Replication NIC).

The above error happens when you didn’t configure a default Gateway (GW) in the TCP/IP properties of the (MAPI NIC).
Solution:

Configure a default gateway in the TCP/IP properties of the (MAPI NIC), Even if it’s a dummy IP,

Make sure that your routing table is proper.