MCDB status is "Offline" and SSDs are not formatted in Exchange Server 2019

Applies to: Exchange Server 2019

Symptoms


Assume that you deploy Microsoft Exchange Server 2019 in Windows Server 2019. You use the Manage-MetaCacheDatabase.ps1 script to enable MetaCacheDatabase (MCDB).
For example:
Manage-MCDB -DagName TestDag1 -ServerAllowMCDB $false -ServerName "exhs-5046" -ForceFailover $true​

Then, you use the Get-MailboxDatabaseCopyStatus cmdlet to view the health and status information for the database copies.​
For example:​
Get-MailboxDatabaseCopyStatus | Fl name, *meta*​

Name : DB01\Server01​
MetaCacheDatabaseStatus : Offline​
MetaCacheDatabaseStatusMessage : Partition not attached in active Store worker process.​
MetaCacheDatabaseFilePath : C:\ExchangeMetaCacheDbs\DB01\DB01.mcdb\DB01-mcdb.edb​
MetaCacheDatabaseLastReset :​
This example returns the status for the copy of database DB01 on Mailbox server Server01.​

In the results, you find that the solid state drive (SSD) is not formatted as expected, and the MCDB status is "Offline". Additionally, not all designated SSDs are formatted, and mount points are not created as expected.

Cause


This issue occurs because of a new behavior in Windows Server 2019 that causes Get-Disk to return all uninitialized discs within the database availability group (DAG) or cluster, and the script incorrectly tries to format an SSD on another DAG member.

Resolution


To fix this issue, install the Cumulative Update 5 for Exchange Server 2019 or a later cumulative update for Exchange Server 2019.

References


Learn about the terminology that Microsoft uses to describe software updates.