Tuesday, June 6, 2017

Cumulative Updates and Recovery Databases

Hi folks,

I want to share about another adventure which I have had with the installation of the latest CU on Exchange 2016. During installation of CU and in particular during configuration of the Mailbox services component installation failed with the error as below:

In couple of words at this stage installation is checking availability of the arbitration mailboxes, and if they're not available, it tries to create them and configure quotas and SCL related settings.

According to this error for some reason Exchange setup program has attempted to configure arbitration mailbox in the recovery database. Probably it was the first retrieved from the list of DBs located on the server and since recovery DB can't store mailboxes setup program had failed.

In my case to solve it I had to remove it by running a command similar the the below:

Get-MailboxDatabase "RecoveryDB001" |Remove-MailboxDatabase -Confirm:$false

After this installation should proceed.

However in my cases there was a problem with AD replication and it was not properly removed from the AD. Therefore the error above would still pop up at every time I tried to re-run the installation program. In the log I have discovered domain controller which install program tried to use and navigated to the path of the DB as below:

CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=CONTOSO,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=contoso,DC=com

After manual deletion of a DB object from the AD installation had proceeded successfully.