Windows XP Clients Cannot Execute Logon Scripts against a Windows Server 2012 R2 Domain Controller – Workaround

Posted on April 25, 2014 by workinghardinit

The issue

The real issue is that you are still running Windows XP. The secondary issue is that you have Windows XP clients that cannot connect to a file share (NETLOGON) on a Windows Server 2012 R2 Domain Controller. If you try manually via \domaincontrollerNetlogon it will throw an error like "The specified network name is no longer available". Security wise & moral pressure wise I kind of think this drives home the message you need to get off Windows XP. But I realize you’re in a pickle so here’s the workaround/fix.

Root Cause & Fix

Windows XP talks SMB 1.0 and that’s it. If this is not offered by the server (file server or domain controller) we have a problem. Now if you installed new Windows Server 2012 R2 servers they do not deploy the SMB 1.0 feature by default. If you upgraded from Windows 2008 R2 (perhaps even over Windows 2012) to get to Windows 2008 (R2) this feature kept in place. Other wise you’ll need to make sure SMB 1.0 is installed, it often (always?) is. Just check.

However there is a big change between Windows Server 2008 R2/Windows 2012. The LanmanServer service has a dependency set to SMB 2.0 and no longer to SMB 1.0

This is what it looks like on a Windows Server 2012 (or lower) domain controller:

This is what it look like on a Windows Server 2012 domain controller

So we need to change that on Windows 2012 R2 to support Windows XP. We can do this in the registry. Navigate to

HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesLanmanServerDependOnService

Change SamSS Srv2 to SamSS Srv
Restart the Server (Lanmanserver) service (it will restart the dependent services like netlogon, DFS Namespace, .. as well)

You’re XP clients should be able to authenticate again. You can test this by navigating to \domaincontrollerNetlogon on a XP client. This should succeed again.

If you have issues with Windows Server 2012 R2 file servers … this is also valid. When you do get rid of Windows XP. Go back to the original settings please Smile .

If you want to read more on SMB read this blog Windows Server 2012 R2: Which version of the SMB protocol (SMB 1.0, SMB 2.0, SMB 2.1, SMB 3.0 or SMB 3.02) are you using? by Jose Barreto (File Server team at Microsoft)

Finally, get off XP!

I think I said it enough on twitter and my blog Legacy Apps Preventing Your Move From Windows XP to Windows 8.1? Are you worried about HeartBleed? Good! Are you worried about still being on XP? No? Well dump SSL and use clear text authentication as XP is a free fire zone anyway (as of April 8th 2014) and it’s just a matter of time before you’re road kill. Any company who has CIO/CTO/IT managers and other well paid functions and have let their organization be held hostage on XP (I’m not talking about a few PCs or VMs left and right) by legacy apps & ISV should realize they are the one who let this happen. Your watch. Your responsibility. No excuses.

Exchange 2010 SP3 Rollup 5 Added Support for Windows Server 2012 R2 Active Directory

Posted on April 7, 2014 by workinghardinit

6 weeks ago (February 25th 2014) Microsoft finally took away the last barrier to upgrading some of our Windows Server 2012 Active Directory Environments to R2. Most of them are still running Exchange 2010 SP3 and not Exchange 2013. The reason is that Exchange 2013 was not deployed is whole other discussion Eye rolling smile .

However that dis mean that until the release of Exchange Server 2010 SP3 Update Rollup 5 last month we could not upgrade Active Directory to Windows Server 2012 R2. Rollup 5 brought us support for exactly that. We can now:

Support Domain Controllers running Windows Server 2012 R2
Raise the Active Directory Forest Function Level and Domain Functional Level to Windows Server 2012 R2

Please note that you cannot deploy Exchange Server 2010 (SP3 RU5) on Windows Server 2012 R2 and you’ll probably never will be able to do that. I’m not sure Microsoft has any plans for this.

Now our office moves have been concluded, meaning I can get back to IT Infrastructure instead of being an glorified logistics & facility peon, we’re doing the upgrade.

This also means we can move the Active Directory environments to the latest version so we have the best possible position for any future IT projects at very low risk. The environments are already at W2K12 functional level. If the budgets get so tight they lose/scrap EA or volume licensing it also allows them to run at this level for many years to come without causing any blocking issues.

Copy Cluster Roles Hyper-V Cluster Migration Fails at Final Step with error Virtual Machine Configuration ‘VM01’ failed to register the virtual machine with the virtual machine service

Posted on March 19, 2014 by workinghardinit

I was working on a migration of a nice two node Windows Server 2012 Hyper-V cluster to Windows Server 2012 R2. The cluster consist out of 2 DELL R610 servers and a DELL MD3200 shared SAS disk array for the shared storage. It runs all the virtual machines with infrastructure roles etc. It’s a Cluster In A Box like set up. This has been doing just fine for 18 months but the need for features in Windows Server 2012 R2 became too much to resists. As the hardware needs to be recuperated and we have a maintenance windows we use the copy cluster roles scenario that we have used so many times before with great success. It’s the Perform an in-place migration involving only two servers scenario documented on TechNet and as described in one of my previous blogs Migrating a Hyper-V Cluster to Windows 2012 R2 for your convenience.

Virtual Machine Configuration ‘VM01’ failed to register the virtual machine with the virtual machine service

As the source host was running on Windows Server 2012 we could have done the live migration scenario but the down time would be minimal and there is a maintenance window. So we chose this path.

So we performed a good health check. of the source cluster and made sure we had no snapshots left hanging around. Yes it’s supported now for this migration scenario but I like to have as few moving parts as possible during a migration.

It all went smooth like silk. After shutting down the VMs on the source cluster node, bringing the CSV off line (and un-presenting the LUN from the source node for good measure), we present that LUN to the target host. We brought the CSV on line and when that was completed successfully we were ready to bring the virtual machines on line and that failed …

Log Name:      Microsoft-Windows-Hyper-V-High-Availability-Admin
Source:        Microsoft-Windows-Hyper-V-High-Availability
Date:          4/02/2014 19:26:41
Event ID:      21102
Task Category: None
Level:         Error
Keywords:
User:          SYSTEM
Computer:      VM01.domain.be
Description:
‘Virtual Machine Configuration VM01’ failed to register the virtual machine with the virtual machine management service.

Let’s dive into the other event logs. On the host the application security and system event log are squeaky clean. The Hyper-V event logs are pretty empty or clean to except for these events in the Hyper-V-VMMS Admin log.

Log Name:      Microsoft-Windows-Hyper-V-VMMS-Admin
Source:        Microsoft-Windows-Hyper-V-VMMS
Date:          4/02/2014 19:26:40
Event ID:      13000
Task Category: None
Level:         Error
Keywords:
User:          SYSTEM
Computer:      VM01.domain.be
Description:
User ‘NT AUTHORITYSYSTEM’ failed to create external configuration store at ‘C:ClusterStorageHyperVStorageVM01’: The trust relationship between this workstation and the primary domain failed.. (0x800706FD)

Bingo. It must be the fact that no domain controller is available. It’s completely self contained cluster and both domain controller virtual machines are highly available and reside on the CSV. Now the CSV does come on line without a DC since Windows Server 2012 so that’s not the issue. it’s the process of registering the VMs that fails without a DC in an Active Directory environment.

Getting passed this issue

There are multiple ways to resolve this and move ahead with our cluster migration. As the environment is still fully functional on the source cluster I just removed a DC virtual machine from high availability on the cluster. I shut it down and exported it. I than copied it over to the node of the new cluster (we’re going to nuke the source host afterwards and install W2K12R2, so we moved it to the new host where it could stay) where I put it on local storage and imported it. For this is used the “Register the virtual machine in-place option”. I did not make it high available.

After verifying that we could ping the DC and it was up and running well we tried the final phase of the migration again. It went as smooth as we have come to expect!

Other options would have been to host the DC virtual machine on a laptop or other server. If you could no longer get to the the DC for export & import or heck even a shared nothing migration depending on your environment can help you out of this pickle. A restore from backup would also work. But here in that 2 node all in one cluster our approach was fast and efficient.

So there you go. Tip to remember. Virtualizing domain controllers is fully supported, no worries there but you need to make sure that if you have a dependency on a DC you don’t have the DC depending on that dependency. It’s chicken an egg thing.

Some Insights Into How Windows 2012 R2 Hyper-V Backups Work

Posted on March 6, 2014 by workinghardinit

How Windows Server 2012 R2 backups differ from Windows Server 2012 and earlier

You’ll remember our previous blog about an error when backing up a virtual machine on Windows Server 2012 R2, throwing this error:

Dealing With Event ID 10103 “The virtual machine ‘VM001’ cannot be hot backed up since it has no SCSI controllers attached. Please add one or more SCSI controllers to the virtual machine before performing a backup. (Virtual machine ID DCFE14D3-7E08-845F-9CEE-21E0605817DC)” In Windows Server 2012 R2

The fix was easy enough, adding a virtual SCSI controller to the virtual machine. But why does it need that now?

Well, this all has to do with the changed way Windows Server 2012 R2 backups work. Before Windows Server 20012 R2 the VSS provider created a VSS snapshot inside the guest virtual machine. That snapshot was exposed to the host, to create a volume snapshot for backup purposes. Right after the volume snapshot has been taken this VSS snapshot inside the guest virtual machine needed to be reverted. The backups then run against that volume snapshot and is consistent thanks to both host & guest VSS capabilities.

For an overview of VSS based backup process in general take a peak at Overview of Processing a Backup Under VSS

Now it is the “Hyper-V Integration Services Shadow Copy Provider” that is being used. When the the host initiates a volume snapshot (Microsoft or hardware VSS provider) the host VSS writer goes in to freeze. This process leverages the Hyper-V Integration Services Shadow Copy Provider to create the virtual machine checkpoint. After that the volume/LUN/CSV snapshot is taken. When that is done the host VSS writes goes into thaw and the virtual machine checkpoint is deleted. After that the backup runs against the Volume snapshot and at the end that is also deleted. You can follow this process quite nicely in the GUI of your Hyper-V host, you SAN (if you use a Hardware VSS provider).

Dear storage vendors: a great, reliable, fast VSS Hardware Provider is paramount to success in a Microsoft environment. You need to get this absolutely right and out of the door before spending any more time and money on achieving yet more IOPS. Keep scalability in mind when doing this.

Dear backup software vendors: think about the scalability when designing your products. If we have 200 or 500 or a thousand VMs … can we leverage CSV based backups to protect every VM on the LUN or do we need to snap the LUN for every VM backed up? Choice there is good for both data protection schemes and scalability.

At this stage the hardware VSS snapshot is being taken …

Contrary to common belief this means that the backup will indeed application consistent to the time of the checkpoint as the CSV snapshot being taken is of a consistent checkpoint. It’s the delta in the active avhdx that is only crash consistent, like any running VM by the way. Now pay attention to the screenshot below. The two red arrows are indicating to ntfs source events, two volumes seem to be exposed to the next free drive letters. E: and F: here as C: is the virtual machine OS and D: the DVD.

Look at the detail. Indeed two. Well it the previous screenshot we only saw one in the CSV path but there are two avhdx files indeed.

Exposing a snapshot on the SAN to a server actually shows us this much better … look here at the avhdx with the GUID and one with “AutoRecovery” in the name. So that makes for two nfts events … and as the backup needs to do this life it requires a vSCSI controller to be present in the virtual machine … and vIDE controller can’t do this.

Anyway, enough under the hood detective work for now, In VEEAM that stage looks like this:

And on the Compellent it looks like this. The screenshots are from different backups at different times so don’t get confused about the time stamps here. It’s just as illustration of what you can expect to see.

Now when the CSV snapshot has been taken the virtual machine checkpoint is removed. At that time the backup runs against the CSV snapshot. In our case (hardware VSS provider) this is a snapshot on the SAN that gets exposed in a view and mapped to the off host backup proxy VEEAM server. On the DELL Compellent it looks like this.

This takes a while to o…but after a while the backup will kick off. Do not that the checkpoint has merged and is no longer visible at this time.

Once the backup is complete, the mapping is removed, the view deleted and the snapshot expired. So your SAN is left as the backup found it.

There you go. I hope this helped clarify certain things on how Hyper-V guest backups work in Windows 2012 R2. So your backups are still application consistent, just not when you’re running Linux or DOS or NT4.0 as there is no support / VSS for that. However they are based on a consistent virtual machine snapshot which explains why Hyper-V backups can protect Linux guests very adequately!

Working Hard In IT

My view on IT from the trenches

Tag Archives: Windows Server 2012 R2