An error occurred trying to connect the WSUS server

You might not expect a WSUS blog post on a site maintained by an Exchange consultant, but there are still customers using Exchange servers on-premises, and these need to be patched as well (and so are the clients of course).

After installing and a new WSUS server running on Windows 2016 I quickly ran into an annoying issue after configuring the WSUS server and downloading the updates. The console would no longer connect and generated a ‘Connection Error’ popup saying “An error occurred trying to connect the WSUS server. This error can happen for a number of reasons. Check connectivity with the server. Please contact your network administrator if the problem persists.”

Error Connection Error

When you click the copy error to clipboard button the following is copied:

The WSUS administration console was unable to connect to the WSUS Server via the remote API.
Verify that the Update Services service, IIS and SQL are running on the server. If the problem persists, try restarting IIS, SQL, and the Update Services Service.
The WSUS administration console has encountered an unexpected error. This may be a transient error; try restarting the administration console. If this error persists, Try removing the persisted preferences for the console by deleting the wsus file under %appdata%\Microsoft\MMC\.

If IISRESET was executed, it runs again for some time, but then the issue happens again. When looking at the IIS console when this error occurs it turns out that the WsusPool was stopped as can be seen in the following screenshot:

WSUS App Pool

Starting the WsusPool solves the problem temporarily, but after some time it stops again. And again… and again…

It turns out to be a private memory issue in the WsusPool which seems to be depleted quickly. It is possible to assign more memory, but since I have no clue how much memory to assign I changed the setting to ‘0’ (1,843,200 KB is default) so the WsusPool can use anything it needs.

WSUS App Pool advanced settings

After changing the private memory limit for the WsusPool the error no longer occurs.

Exchange 2019 on Windows Server Core disk management

When installing an Exchange 2019 Edge Transport server on Windows 2019 Server core I realized there’s no disk management MMC snap-in, so all disk configuration needs to be done using PowerShell.

For this blogpost I added a 20GB disk to my Windows 2019 Server Core server which I want to use as a D:\ drive for my SMTP queue.

You can use the Get-Disk command to retrieve the server’s disk configuration, and you can pipe this disk object into the Initialize-Disk command to bring it online and assign a new partition:

Get-Disk –Number 1 | Initialize-Disk –PartitionStyle GPT New-Partition –DiskNumber 1 –UseMaximumSize

Initialize-Disk

By default, Windows installs on drive C:\ and the DVD is mounted as drive D:\. You can use the Get-WmiObject and the Set-WmiInstance commands to assign it a different drive letter, for example drive Z:\

Get-WmiObject -Class Win32_volume -Filter ‘DriveType=5′ | Select -First 1 | Set-WmiInstance -Arguments @{DriveLetter=’Z:’}

The next step is to assign drive letter D:\ to the newly added disk:

Add-PartitionAccessPath -DiskNumber 1 -PartitionNumber 2 –AccessPath “D:\”

And finally format it using NTFS file system and a block size of 64KB:

Get-Partition –Disknumber 1 –PartitionNumber 2 | Format-Volume –FileSystem NTFS –NewFileSystemLabel “Queue” -AllocationUnitSize 65536 –Confirm:$false

format-disk

Now you can continue with the standard installation procedure for an Exchange 2019 Edge Transport server (which does not differ from an Exchange 2013 or Exchange 2016 Edge Transport server)

DNS Suffix Windows 2019 Server Core

While preparing a Windows 2019 Core server for an Exchange 2019 Edge Transport server I had to set the FQDN of the server. The server name itself is not difficult, you can change this using the SCONFIG tool, but you cannot change the DNS suffix using SCONFIG.

For changing the DNS suffix on a Windows 2019 Core you can use the NETDOM, the REG.EXE or PowerShell:

netdom computername %computername% /makeprimary:%computername%.exchangelabs.nl

or when using the computer name itself:

netdomain computername AMS-EDGE01 /makeprimary:AMS-EDGE01.exchangelabs.nl

To add the registry key needed for the DNS suffix (HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Domain\NV Domain) you can also use the REG.EXE tool:
reg.exe add HKLM\SYSTEM\CurrentControlSet\services\Tcpip\Parameters /v “NV Domain” /t REG_SZ /d “exchangelabs.nl” /f

Or you can use PowerShell:

New-ItemProperty -Path “HKLM:\ SYSTEM\CurrentControlSet\services\Tcpip\Parameters\” -Name “NV Domain” -PropertyType REG_SZ -Value “exchangelabs.nl”

New-ItemProperty DNS Suffix

Reboot the server, run IPCONFIG /ALL and you’ll see the DNS suffix. The server can now be used for installing Exchange 2019 Edge Transport server.
ipconfig all