Meta Cache Database (MCDB) Setup Guide is available

[The_Exchange_Team]

At Ignite 2017 and 2018 we began telling you about the Meta Cache Database feature we’re using in the O365 cloud service to improve scenario performance and store more mailboxes on ever-growing hard disk drives (HDDs). If you have not had a chance to join us at Ignite or would like a refresher, here are the two sessions:

• Ignite 2017 – Exchange High Availability and Storage for Insiders
• Ignite 2018 – Email search in a flash! Accelerating Exchange 2019 with SSDs

For those of you who have been itching to try this out, there’s good news! Not only did we ship MCDB in the Exchange Server 2019 release, we now also have a setup guide available that outlines how you can use a new PowerShell script cmdlet to deploy this feature. For all the details, head on over to Microsoft Docs and read on: MetaCacheDatabase (MCDB) Setup Guide If you have questions or feedback, please let us know. Tobias Klima

[christianschul]

Hi,

thanks for the guide but it is really poor and basic. No deep description and no trouble shooting infos. No description how to check if MCDB disk is available (get-disk, get-physicaldisk // media type: ssd - Partition Style: raw) - only an error:
Call-ConfigureMCDBOnServer : The specified number of SSD devices could not be integrated. The drives are are not present as configured, or they are unformatted devices (raw). (translated from german)

Is SSDSizeInBytes at the ConfigureMCDBOnServer for the partition size or to identify the disk to use?!?

Ok, got it for the first server and it was fine - disk prepared and mountpoint at C:\ was created. But I did not get the last green message "MetaCacheDatabase status for x is Storageoffline, successfully completed MCDB Setup for x on Server x":

...but looks fine?!? Now I wanted to do the same on the second dag member and got a success message but the disk was not prepared and no mount point. The message was much shorter - no table but the green message which I missed at the other server:

MCDB Status was now "Storage Offline" like you described and I moved the active database. Nothing happens and the MCDB message at the Database sounds not good: "Directory xxx is not configured as a mountpoint"

What is the issues and what was not configured correct?

Some issues at the guide:

• False: Manage-MCDB -DagName TestDag1 -ServerAllowMCDB $true -ServerName "exhs-5046"
  Correct: Manage-MCDB -DagName TestDag1 -ServerAllowMCDB:$true -ServerName "exhs-5046"
  
• Failover cannot be done with Manage-MCDB -ServerAllowMCDB:$true -ForceFailover:$true - there will no failover done
  
  
• At the picture step 3:
  "TestEnv" is not available Manage-MCDB

Did someone really test the guide and checked it? MCDB is a great feature but the implementation is horrible at the moment...

How can assist?

Thanks 
Christian 

[gkolosov]

Ran into the exact same issue :(

Have you managed to proceed or have you abandoned this project?

[cschulenburg]

I did not go on on that...

best 

Christian

[gkolosov]

Hi Christian,

I might have found a solution.

Looking at my Exchange update version, I am running CU1.

Latest EX2019 update is CU5, and it seems like they have fixed a few things in MCDB CMDLET.

Unfortunately to download CU5, Microsoft requires you to have a Volume License subscription, and I do not have that.
https://support.microsoft.com/en-nz/help/4537677/cumulative-update-5-for-exchange-server-2019

Hopefully this helps you provided you have the right subscription!