Fixing Hiccups in The SCVMM2008R2 GUI & Database

As you might very well know by experience sometimes the System Center Virtual Machine Manager GUI and database get out of sync with reality about what’s going on for real on the cluster. I’ve blogged about this before in SCVMM 2008 R2 Phantom VM guests after Blue Screen and in System Center Virtual Machine Manager 2008 R2 Error 12711 & The cluster group could not be found (0×1395)

The Issue

Recently I had to trouble shoot the “Missing” status of some virtual machines on a Hyper-V cluster in SCVMM2008R2. Rebooting the hosts, guests, restarting agents, … none of the usual tricks for this behavior seemed to do the trick. The SCVMM2008R2 installation was also fully up to date with service packs & patches so there the issue dot originate.

Repair was greyed out and was no use. We could have removed the host from SCVMM en add it again. That resets the database entries for that host en can help fix the issues but still is not guaranteed to work and you don’t learn what the root cause or solution is. But none of our usual tricks worked.We could have deleted the VMs from the database as in  but we didn’t have duplicates. Sure, this doesn’t delete any files or VM so it should show up again afterwards but why risk it not showing up again and having to go through fixing that.

The Cause

The VMs were in a “Missing” state after an attempted live migration during a manual patching cycle where the host was restarted the before the “start maintenance mode” had completed. A couple of those VMs where also Live Migrated at the same time with the Failover Cluster GUI. A bit of confusion al around so to speak nut luckily all VMs are fully operational an servicing applications & users so no crisis there.

The Fix

DISCLAIMER

I’m not telling you to use this method to fix this issue but you can at your own risk. As always please make sure you have good and verified backups of anything that’s of value to you Smile

We hade to investigate. The good news was that all VMs are up an running, there is no downtime at the moment and the cluster seems perfectly happy Smile.

But there we see the first clue. The Virtual machines on the cluster are not running on the node SCVMM thinks they are running, hence the “Missing” status.

First of all let’s find out what host the VM is really running on in the cluster and see what SCVMM thinks on what host the VM  is running. We run this little query against the VMM database. That gives us all hosts known to SCVMM.

SELECT [HostID],[ComputerName] FROM [VMM].[dbo].[tbl_ADHC_Host]

HostID                                                                        ComputerName

559D0C84-59C3-4A0A-8446-3A6C43ABF618          node1.test.lab

540C2477-00C3-4388-9F1B-31DBADAD1D8C        node2.test.lab

40B109A2-9E6B-47BC-8FB5-748688BFC0DF         node3.test.lab

C2DA03CE-011D-45E3-A389-200A3E3ED62E        node4.test.lab

6FA4ABBA-6599-4C7A-B632-80449DB3C54C         node5.test.lab

C0CF479F-F742-4851-B340-ED33C25E2013          node6.test.lab

D2639875-603F-4F49-B498-F7183444120A             node7.test.lab

CE119AAC-CF7E-4207-BE0B-03AAE0371165         node8.test.lab

AB07E1C2-B123-4AF5-922B-82F77C5885A2           node9.test.lab

(9 row(s) affected)

Voila en now the fun starts. SCVMM GUI tells us “MissingVM” is missing on node4.

We check this in the database to confirm:

SELECT Name, ObjectState, HostId
FROM VMM.dbo.tbl_WLC_VObject
WHERE Name = 'MissingVM'
GO

Which is indeed node4

Name                                                                                                                                                                                                                                                             ObjectState HostId

———  —  ————————————

node4  220  C2DA03CE-011D-45E3-A389-200A3E3ED62E

(1 row(s) affected)


In SCVMM we see that the moving of the VM failed. Between node 4 and node 6.

image

Now let’s take a look at what the cluster thinks … yes there it is running happily on node 6 and not on node 4. There’s the mismatch causing the issue.

So we need to fix this. We can Live Migrate the VM with the Failover Cluster GUI to the node SCVMM thinks the VM still resides on and see if that fixes it. If it does, great! You have to give SCVMM some time to detect all things and update its records.

But what to do if it doesn’t work out?  We can get the HostId from the node where the VM is really running in the cluster, which we can see in the Failover Cluster GUI, from the query we ran above and than update the record:

UPDATE VMM.dbo.tbl_WLC_VObject
SET HostId  = 'C0CF479F-F742-4851-B340-ED33C25E2013'
WHERE Name = 'MissingVM'
GO

We then reset the ObjectState to 0 to get rid of the Missing status. It would do this automatically but it takes a while.

UPDATE VMM.dbo.tbl_WLC_VObject
SET ObjectState = '0'
WHERE Name = 'MissingVM'
GO

After some patience & Refreshing all is well again and test with live migrations proves that all works again.

As I said before people get creative in how to achieve things due to inconsistencies, differences in functionality between Hyper-V Manager, Failover Cluster Manager and SCVMM 2008R2 can lead to some confusing situations. I’m happy to see that in Windows 8 the action you should perform using the Failover Cluster GUI or PowerShell are blocked in Hyper-V Manager. But SCVMM really needs a “reset” button that makes it check & validate that what it thinks is reality.

Integration Services Version Check Via Hyper-V Integration/Admin Event Log

I’ve written before (see "Key Value Pair Exchange WMI Component Property GuestIntrinsicExchangeItems & Assumptions") on the need to & ways with PowerShell to determine the version of the integration services or integration components running in your guests. These need to be in sync with the one running on the hosts. Meaning that all the hosts in a cluster should be running the same version as well as the guests.

During an upgrade with a service pack this get the necessary attention and scripts (PowerShell) are written to check versions and create reports and normally you end up with a pretty consistent cluster. Over time virtual machines are imported, inherited from another cluster of created on a test/developer host and shipped to production. I know, I know, this isn’t something that should happen, but I don’t always have the luxury of working in a perfect world.

Enough said. This means you might end up with guests that are not running the most recent version of the integration tools. Apart from checking manually in the guest (which is tedious, see my blog "Upgrading a Hyper-V R2 Cluster to Windows 2008 R2 SP1" on how to do this) or running previously mentioned script you can also check the Hyper-V event log.

Another way to spot virtual machines that might not have the most recent version of the integration tools is via the Hyper-V logs. In Server Manager you drill down in the “Diagnostics” to, “Event Viewer” and than navigate your way through  "Applications and Services Logs", "Microsoft", "Windows" until you hit “Hyper-V-Integration

image

Take a closer look and you’ll see the warning about 2 guests having an older version of the integration tools installed.

image

As you can see it records a warning for every virtual machine whose integration services are older than the host running Hyper-V. This makes it easy to grab a list of guest needing some attention. The down side is that you need to check all hosts, not to bad for a small cluster but not very efficient on the larger ones.

So just remember this as another way to spot virtual machines that might not have the most recent version of the integration tools. It’s not a replacement for some cool PowerShell scripting or the BPA tools, but it is a handy quick way to check the version for all the guests on a host when you’re in a hurry.

It might be nice if integration services version management becomes easier in the future. Meaning a built-in way to report on the versions in the guests and an easier way to deploy these automatically if there not part of a service pack (this is the case when the guest OS and the host OS differ or when you can’t install the SP in the guest for some application compatibility reason). You can do this in bulk using SCVMM and of cause Scripting this with PowerShell comes to the rescue here again, especially when dealing with hundreds of virtual machines in multiple large clusters. Orchestration via System Center Orchestrator can also be used. Integration with WSUS would be another nice option, for those that don’t have Configuration Manager or Orchestrator but that’s not supported as far as I know for now.

KB 2636573: Guest Crashes with Win2008R2 RTM/SP1 STOP 0xD1 in storvsc!StorChannelVmbusCallback During Live Migration

The BSOD

I helped hunt down this bug and tested the private fix. Some months ago, during the summer of 2011, I was putting some new Hyper-V clusters under stress tests. You know, letting it work very hard for a longer period of time to see if anything falls off or goes “boink". It all looked pretty robust and and after some tweaking also very fast. Just when you’re about to declare “we’re all set” here you see a BSOD on one of the guests that’s being live migrated happily announcing: “DRIVER_IRQL_NOT_LESS_OR_EQUALSTOP: 0x000000D1 (0×0000000000000000, 0×0000000000000000, 0×0000000000000000, 0×0000000000000000)”

image

Now that doesn’t make ME very happy however. So I investigate to see if there are any more VMs dropping dead during live migration but we don’t see any. Known issues like out of date versions of the integration tools or the like are not in play nor are any other possible suspects.

We throw the MEMORY.DMP file in the debugger and we come up with the following culprit:

DRIVER_IRQL_NOT_LESS_OR_EQUAL (d1)

The driver probably at fault is storvsc.sys

Probably caused by : storvsc.sys ( storvsc!StorChannelVmbusCallback+2b8 )

Hmmmmmmm, we start searching the internet but we don’t find much. We also throw it on to Twitter to see if the community comes up with something. Meanwhile we keep looking and find this little blog post by a Microsoft support engineer Rob Scheepens:

http://blogs.technet.com/b/dip/archive/2011/10/21/win2008r2-rtm-stop-0xd1-in-storvsc-storchannelvmbuscallback-0x2b5.aspx

We pinged Rob and opened a case with MS support. That evening Hans Vredevoort (www.hyper-v.nu), who saw my tweet, mails me with the details of a fellow MVP in the USA having this same issue. We get in contact an via both Microsoft & the Hyper-V community we start hunting the cause of this bug. The progress on this issue can be read at the Microsoft blog above. You’ll notice that the fix is in the works now.

Hunting down the STOP error

What did we establish:

  • It only happens occasionally with a live migration and it rather ad hoc, not every time, not after X amount of live migrations or X amount of up time.
  • It seems sometimes to happens only with guests running dynamically expanding VHDs attached to ISCSI controllers in Hyper-V.  But that’s not really the case as I remember one being with  fixed VHD attached to an SCSI controller. In our case the VMs we could reproduce the issue with in a reasonable time were all SQL Server test and development guests running SQL Server 2008 where the dynamically expanding disks are used as “poor man’s thin provisioning”.
  • I have not heard of this on Windows 2008 hosts, only R2, but I have not tested this.

So it’s reproducible but it takes intensive live migration activity. Meanwhile we received private instrumentation to install on both guests & hosts to collect “enriched” memory.dumps when a guest experiences a BSOD. With PowerShell we have continuous live migration running to reproduce the issue. The fact that can live migrate over 10Gbps does help Smile. Because you can get lucky but in reality needs many hundreds of live migration to reproduce it. On some machines many thousands. Not a joke but I total we did 8000 Live migrations to test the fix and we did about 12000 to reproduce the issue on several VMs with different configurations to send memory dumps to MSFT. So yes, you really need some PowerShell and having a 10Gbps Live Migration network also helps Winking smile.

All the collected MEMORY.DMP files form these live migration exercises were uploaded to Microsoft for analysis. That took a while, also because they had a boatload of live migrations to do and I don’t know if their test lab has 10 Gbps.

On Tuesday the 25th of October Microsoft contacts us with good news. They have root-caused the problem and a hotfix is in the works. You can download that here http://support.microsoft.com/kb/2636573

On Thursday 27th of October we get access to a private fix and after installing this one we’ve been running thousands of live migrations without  seeing the issue.

The public release of this hotfix is currently planned (HTP11-12) under KB2636573.

The details for the curious

Root Cause?

The root cause can be summarized as follows: “StorVSP was modifying guest memory while the VM’s virtual motherboard was being powered off.” Doing this storvsc access a NULL pointer in a memory buffer that is already freed up. The result of this is a BSOD or STOP error in the virtual machine.

Only SCSI attached VHDs

OK but why do we only see this with SCSI attach VHDs? Now the issue happens during power down of the virtual machines’ mother board because there is a disk enumeration during the shut down phase. And this enumeration only happens with SCSI disks.

Right! So the more VHDs we had attached to SCSI controllers in a virtual machine the higher the likelihood of this happening.

Why so much more likely with dynamically expanding VHDs

But still we saw this exponentially more with dynamically expanding disks. Why is that? Well it’s not that dynamically expanding disks trigger disk enumeration more than fixed disks.  However it seems that any disk expansion, which causes write delays, can lead to a timing issue that will cause the disk enumeration to hit the issue described above. So this significantly increases the risk that the STOP error will happen and it explains that the chance this will happen with fixed VHDs attached to SCSI controllers is significantly lower. This is sync with what we saw. The virtual machines with a lot of dynamic disks attach to SCSI controllers that had a lot of activity (and thus potential for expanding) is the ones where we could reproduce this the fasted.

Conclusion

It can take some time to hunt down certain bugs, especially the rare ones that only happen every now and then so occurrences are few and far between. But when you put in some effort Microsoft helps out and works on a fix. And no you don’t have to have the most expensive support contract for that to happen. As a  matter of fact this call was logged under a free support call with the TechNet Plus subscription. And as it was a bug, they return it as unused.

KB2616676 Patching Hiccup Discovered by Out of Sync Cluster Nodes

I was investigating an issue on a Windows 2008 R2 SP1 cluster and as part of my check list I ran the cluster validation. Than came out clean but for the fact that it complained about an update that was missing on some of the nodes.

That update was Microsoft Security Advisory: Fraudulent digital certificates could allow spoofing or KB2607712 Not that these cluster nodes are web clients but this is not good and we need to have this fixed for both security & cluster supportability reasons.

But neither WSUS or Windows Update indicate that there is an update available for these nodes. So I download the patch manually and try to install it. Then I get the response: ‘This update is not applicable to your computer’

No good! Now we need to find out what’s up. After some searching we find other people with this issue in the Microsoft forums: KB2607712 does not download to clients.

As it turns out KB2607712 was erroneously marked as superseded by KB2616676. This means that if that update is approved, or installed, the download/installation of KB2607712 is blocked. I check this on the nodes involved and this is indeed the case.

No please now that the forum reply states “erroneously marked as superseded” which means that BOTH updates are needed. The work around is to:

  • uninstall/unapprove KB2616676
  • install/approve KB2607712
  • reinstall/approve  KB2616676  again after you clients/host have KB2607712 installed.

There should be a revision of KB2616676 coming in the future that’s to include of KB2607712, meaning that KB2607712 will truly be supersede by it. As of this writing that revised version is not released yet so you’re left with the workaround until now.

Piece of advice. Keep your cluster nodes patched but do it in a well organized matter so they remain in sync.  Don’t just do half of the nodes. The good thing that came out of this that we discovered that some other servers/clients did not get the update for KB2607712 due to this. So now the company can address this issue using the workaround. I did the manual uninstall/reinstall workaround for the cluster nodes. For their clients an other servers  I suggested they’d go the WSUS way.

Using Host Names in IIS in Combination with a KEMP LoadMaster

At a client the change over of a web site from old servers to new ones lead to the investigation of an issue with the hardware load balancer. Since that web site is related to an existing surveyors solutions suite that already had a KEMP LoadMaster 2200 in use the figured we’d also use it for the web site and no longer use WNLB.

Now the original web site had multiple DNS entries and host header names defined in IIS (see Configure a Host Header for a Web Site (IIS 7)) . Host header names in IIS allow you to host multiple web sites on an IIS server using the same IP address and port. A small added security benefit is that surfing on IP address fails which means we marginally disrupt some script kiddies & get an extra security checkbox marked during an audit Winking smile.

In our example we needed:

  • ntrip.surveyor.lab
  • www.surveyor.lab

Note: The real names have been changed as well as the reasons why as this has some business & historical justifications that don’t matter here.

ntrip.surveyor.lab needs to be handled by the load balanced web servers in the solution. The www.surveyor.lab needs to be redirected to another web server to keep the business happy. However for political reasons we have to keep the DNS record for www.surveyor.lab pointing to the load balanced servers, i.e. the load master VIP.

Now without host names IIS al worked fine until we wanted to use HTTP redirect. As the web site is the same IP address for both names we either redirected them both or none. To fix this we needed two sites in IIS. The real one hosting ntrip.surveyor.lab and a “fake” one hosting the www.surveyor.lab that we want to redirect. Well as both are hosted on the same IP address and port on the IIS server we need to use host names. But then the sites became unavailable.

When checking the LoadMaster configuration, the virtual service for the web servers seemed well.

image

Is this a limitation of hardware load balancing or this specific Loadmaster? Some searching on the internet made it look like I was about the only on on the planet dealing with this issue so no help there.

Kemp Support Rocks

I already knew this but this experience reaffirms it. KEMP Technologies really does care about their customers and are very fast & responsive. I threw a quick question on twitter to @KempTech on Twitter and they responded very fast with some pointers. After that I replied with some more details, they offered to take it on via other means as twitter has it limits. OK, no problems. The next morning I got an e-mail from one of their engineers (Ekkehard) with more information and a request for more input from our side. I quickly made a VISIO diagram of the current and the desired situation. Based on this he let me know this should work.

image

He asked for a copy of the configuration and already pointed to the solution:

And what exactly happens – does the RS turn “red” in the “View/Modify Services” view? That might be caused by the health check settings…
(Remember that a 302 is considered NOT ok, so you had to enter the proper check URL and or / HTTP1.1 hostname)

But at that moment I did not realize this yet. I saw no error or the real server turning red indicating it was down. So we went through the configuration and decided to test without forcing layer 7 to see what happened. This didn’t make a difference and it wasn’t really a solution if it had as we needed layer 7 and layer 7 transparency.

Ekkehard also noticed my firmware was getting rather old (don’t fix what isn’t broken Smile) and suggest an upgrade (5.1-24 to 5.1.-74). So I did, reboot and tested some more settings. To make sure I didn’t miss anything I threw a network sniffer (WireShark) against the issue. And guess what?  As soon as I added a host name to the IIS web site bindings I didn’t even get any request from my client on that server anymore. So it was definitely being stopped at the Loadmaster. Without it request from a client came through perfectly.  That was not IIS doing as with a host name nothing came into the server. So why would the LoadMaster stop traffic to a real server? Because it’s down, that’s why, just like Ekkehard has indicated in one of his mails but we didn’t see it then.

Better check again and sure enough, the health service told me the real servers are down. Hey … that’s new. Did the previous firmware not show this, or just slower? I can’t say for sure. It’s either me being to impatient, a hiccup, the firmware or premature dementia Confused smile

Root Cause

So what happens? The default health check uses HTTP 1.0. You can customize it with a path like  /owa or such but in essence it uses the IP address of the real server and guess what. With a Host header name in IIS that isn’t allowed other wise it can’t figure out what website you want to go to if you’re using this feature to run multiple sites on the same IP address and port. So we need to check the health based on host name. Can the LoadMaster do that for us? Yes it can!

The fix

You need to enable HTTP 1.1 and fill out the host name you want to use for health checking.  In our case that’s ntrip.surveyor.lab. That’s all there’s to it. Easy as can be if you know. And Ekkehard knew he indicated to this in his quoted mail above.

HTTP1 1host

 

Lessons Learned

So how did I not know this? Isn’t this documented? Sure enough on page  56 of the LoadMaster manual it says the following:

7  HTTP  The LoadMaster opens a TCP connection to the Real Server on the Service port (port80). The LoadMaster sends a HTTP/1.0 HEAD request the server, requesting the page ―/‖.  If the server sends a HTTP response with a status code of 2 (200-299, 301, 302, 401) the LoadMaster closes the connection and marks the server as active.  If the server fails to respond within the configured response time for the configured number of times or if it responds with a different status code, it is assumed dead.  HTTP 1.0 and 1.1 support available, using HTTP 1.1 allows you to check host header enabled web servers.

Typical, you read the exact line of information you need AND understand it after having figured it out. Now linking that information (yes we always read all manuals completely Embarrassed smile) to the situation at hand isn’t always that fast a process but I got there in the end with some help from KEMP Technologies.

One hint is perhaps to mention this is in the handy tips that pop up when you hover over a setting in the LoadMaster console. I rely on this a lot and a mention of “HTTP 1.1 allows you to check host header enabled web servers” might have helped me out. But it’s not there. A very poor excuse I know … Embarrassed smile

image

Host Header Names & HTTP redirection

After having fix this issue I proceeded to configure HTTP redirect in IIS 7.5. For this is used two sites. One was just a fake site tied to the www.surveyors.lab hostname in IIS on port 80.

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For this site I created a HTTP redirect to www.bussines.lab/surveyors/services. This works just fine as long as you don’t forget the http:// in the redirect URL.

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So it has to be http://www.bussines.lab/surveyors/services or you’ll get a funky loop effect looking like this:

http://www.surveyors.lab/www.bussines.lab/surveyors/services/www.bussines.lab/surveyors/services/www.bussines.lab/surveyors/services

Firefox will tell you you have a loop that will never end but Internet Explorer doesn’t, it just fails. You do get that URL as a pointer to the cause of the issue. That is if you can relate it to that.

The other was the real site  and was configured with following bindings and without redirection.

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Don’t forget to do this on all real servers in the farm! The next thing I need to find out is how to health check two host names in the LoadMaster as I have two websites with the same IP address, port but different host names.

System Center Virtual Machine Manager 2008 R2 Error 12711 & The cluster group could not be found (0×1395)

The Issues

I recently had to go and fix some issues with a couple of virtual machines in SCVMM 2008 R2. There was one that failed to live migrate with following error:

Error (12711)
VMM cannot complete the WMI operation on server HopelessVm.test.lab because of
error: [MSCluster_ResourceGroup.Name=" df43bf60-7216-47ed-9560-7561d24c7dc8"] The cluster group could not be found.

(The cluster group could not be found (0×1395))
 
Recommended Action
Resolve the issue and then try the operation again

Other than that it looked fine and could be managed with SCVMM 2008 R2. Another one was totally wrecked it seemed. It was in a failed state after an attempted live migration. You couldn’t do anything with it anymore. Repair was “available” but every option there failed so basically that was the end of the game with that VM. Both issues can be resolved with the approach I’ll describe below.

The Cause

After some investigation the cause of this was the fact that this virtual machine had been removed from the failover cluster as a resource was exported & imported using Hyper-V manager on one of the cluster nodes. It was then added back to the failover cluster again to make them high available. All this was done without removing it from SCVMM 2008 R2. By the way, as mentioned above in “The Issues” this can get even worse than just failing live migrations. The same scenario can lead to virtual machines going into a failed state that you can’t repair (retry or undo fail) or ignore and basically you’re stuck at that point. You can’t even stop, start, shutdown the virtual machine anymore, not one single operation works in SCVMM while in the failover cluster GUI and in hyper-v manager everything is fully operational. This is important to note, as the services are fully on line and functional. It’s just in SCVMM that you’re in trouble.

Why did they do it this way? They did it to move the VM to a new CSV. The fact that you delete the VM files when deleting a VM with SCVmm2008R2 made them use Hyper-V manager instead. Now this approach (whatever you think of it) can work but then you need to delete the VM in SCVMM2008R2 after exporting the virtual machine AND before proceeding with the import and making the virtual machine highly available.

People get creative in how to achieve things due to inconsistencies, differences in functionality between Hyper-V Manger and SCVMM 2008R2 (in the latter especially the lack of complete control over naming, files & folders, export/migration behavior) as well as the needs of the failover cluster can lead to some confusing scenarios.

The Supported Fix

Now the easy way to fix this is to export the virtual machine again and delete it in SCVMM 2008 R2. That will remove the virtual machine object from SCVMM, the failover cluster en Virtual Machine Manager. However this virtual machine was so large (50Gb + 750 GB data disk) that there was no room for an export to be made. Secondly an export of such a large VM takes a considerable time and it has to be off line for this operation. This is annoying as SCVMM might be uncooperative at this point, the virtual machine is online en performing it’s duties for the business. So this presented us with a bit of a problem. Stopping the virtual machine, Exporting it using Hyper-V Manager will cause it to go missing in SCVMM 2012 and then you can delete it, importing the virtual machine again and adding it to the failover cluster causes down time.

The Root Cause

Why does this happen? Well when you import a virtual machine into a failover cluster is creates a new unique ID for the virtual machine Resource Group . This happens always. Choosing to reuse an existing ID during import in Hyper-V Manager has nothing to do with this. But VMM uses ID/names to identify a VM, independent of the cluster. So when you did not remove the VM from SCVMM before adding the VM back to the cluster you get a different cluster group ID in the cluster than you have in SCVMM. They both have the same name but there is a disconnect leading to the issues described above.

By the way exporting & importing a VM without first removing the virtual machine from the failover cluster leads to some issues in the Failover cluster so don’t do that either Smile

The “No Down Time” Fix

This is not the first time we need to dive in to the SCVMM database to fix issues. One of my main beef about SCVMM other than inconsistency with the other tools and its lack of control & options in some scenarios is the fact that it doesn’t have enough self-maintenance intelligence & functionality. This leads to the workaround above which are slow and rather annoying or consist of messing around in the SCVMM database, which isn’t exactly supported. Mind you Microsoft has published some T-SQL to clean up such issues themselves. See You cannot delete a missing VM in SCVMM 2008 or in SCVMM 2008 R2 and RemoveMissingVMs. See also my blog SCVMM 2008 R2 Phantom VM guests after Blue Screen post on this subject.

The usual tricks of the trade like refreshing the virtual machine configuration in the failover cluster GUI don’t work here. Neither does the solution to this error described Migrating a System Center Virtual Machine Manager 2008 VM from one cluster to another fails with error 12711. The error is the same but not the cause.

# Add the VMM cmdlets
Add-PSSnapin microsoft.systemcenter.virtualmachinemanager

# Connect to the VMM server
Get-VMMServer –ComputerName MySCVMMServer.test.lab

# Grab the problematic VM and put it into the object $vm
$vm = Get-VM –name “HopelessVM”

#Force a refresh
refresh-vm -force  $vm

In the end we have to fix the mismatch between the VMResourceGroupID in failover cluster and SCVMM by editing the database.

First you navigate to the registry key HKEY_LOCAL_MACHINE\Cluster\Groups\ on one the cluster nodes, do a find for the problematic VM’s name and grab the name of its key, this is the VMResourceGroupID the cluster knows and works with? So now we have the correct VMResourceGroupID: 0f8cabe4-f773-4ae4-b431-ada5a3c9926c

clip_image002

Now you connect to the SCVMM database and run following query to find the VMResourceGroupID that SCVMM thinks that VM has and that it uses causing the issues

SELECT  VMResourceGroupID  FROM tbl_WLC_VMInstance WHERE ComputerName = 'hopelessVM.test.lab'
GO 

The results:

VMResourceGroupID

————————————————–

df43bf60-7216-47ed-9560-7561d24c7dc8

(1 row(s) affected)

The trick than is to simply update that value to the one you just got from the registry by running:

UPDATE tbl_WLC_VMInstance SET VMResourceGroupID = '0f8cabe4-f773-4ae4-b431-ada5a3c9926c' WHERE VMResourceGroupID = 'df43bf60-7216-47ed-9560-7561d24c7dc8'
GO 

Than you need some patience & refresh the GUI a few times. Things will turn back to normal, but in between you might seem some “missing” statuses appear for your problematic VM. These go away fast however. If not you can always use the Microsoft provided script to remove missing VM’s as mentioned above in RemoveMissingVMs.

Warning

What I described above is something you can do to fix these issues fast and effectively when needed. But I’m not telling you this is the way to go, let alone that this is supported. Make sure you have backups of your VMs, Hosts, SCVMM database etc. It only takes one mistake or misinterpretation to royally shoot yourself in your foot Winking smile. It hurts like hell; recovery is long and seldom complete. On top of that it might generate a vacancy in your company whilst you’re escorted out of the building. Be careful out there.

WDeployConfigWriter Account Issues – Trouble Shooting Web Deploy 2.0 With Lessons Learned

Here’s a small recap of a trouble shooting incident we dealt with recently and that served as a coaching exercise for trouble shooting. It seems we have Web Deploy 2.0 in use for in house deployments of web apps. It seems to be a valued asset as well. At least valuable enough to land a help request on the desk of one of the young, eager, smart and upward mobile IT Professionals when it stops working and they need some assistance.

Hello ICT,

To deploy our we websites remotely we use web deployment service (see http://technet.microsoft.com/en-us/library/dd569087(WS.10).aspx for more info).

This service runs under the network service account by default. Deploying fails now. In the security log on the server I find  "The specified account’s password has expired".

Does anyone know the password of this account?

Best regards,

Hardworking Web Guy In Trouble

Basically we have enough information to know something went wrong and that they need it to work again. But that’s about it. Password for the network service account expired? They also included an error log and reading it learns us something. The lesson to be learned here: investigate yourself, read the log, interpret them. Don’t let patients give you a diagnosis. Their input is critical, but you need to draw your own conclusions.

An account failed to log on.

Subject:
                Security ID:                           LOCAL SERVICE
                Account Name:                    LOCAL SERVICE
                Account Domain:                NT AUTHORITY
                Logon ID:                              0x3e5

Logon Type:                                         8

Account For Which Logon Failed:
                Security ID:                           NULL SID
                Account Name:                    WDeployConfigWriter
                Account Domain:                lab.test

Failure Information:
                Failure Reason:                     The specified account’s password has expired.
                Status:                                0xc000006e
                Sub Status:                            0xc0000071

Process Information:
Caller Process ID: 0x1f44
Caller Process Name: C:\Windows\System32\inetsrv\WMSvc.exe

What did we just read and learn? No it’s not the Network Service Account whose password has expired. This doesn’t happen/doesn’t work that way … so that was our first indication that this isn’t quite right in the support ticket. As you can see the real problem account mentioned in the error log:  WDeployConfigWriter. That account is indeed a local account.

WdeployAccounst

 

Cool, now we check what service runs under that account by looking in the services panel …. none! The easy way to check is to sort on the "Log On As" column. You won’t find WDeployConfigWriter. Right … , what else do we learn from the Services panel. Well we do have service called Web Deployment Agent Service running under the local Network Service account. We can stop and start it just fine so there is nothing wrong with the Network Service account , which is as expected and this service is not our culprit.  What we also learn that this is Web Deploy 2.0.

Service

 

As the Web Deployment Agent Service has nothing to do with the problem at hand. So where is that WDeployConfigWriter being used and what is it status? Let’s take a look.

WdeployAccountsettings

 

Hey, how could this account have expired? This is impossible. Unless they changed it while trying to fix the error. We check this with  quick phone call and yes, they did exactly that.  The good thing is that this web guy is professional and tells us what they did. Some people think this might get them into trouble and won’t do that. It doesn’t change anything, things are what they are, but it does make communication less easy when you discover people act that way… So the lessons here are to double check & verify what happened if at all possible. Originally the settings were:

WDeployAccountOriginalSettings 

 

They changed them after they ran into issues hop that checking those options might fix it. Well no, expired is expired and you can’t fix it like that. You need indeed to correct the settings if you don’t want the password to expire and even prevent the user from changing it but you also need to set a new password when it has already expired. After doing so we contact the hardworking web guy in trouble to let ‘m test and predict a new error: whatever runs under that Account will now fail to run due to an incorrect password. And guess what? “Unknown user name or bad password” in the security log.

Log Name:      Security
Source:        Microsoft-Windows-Security-Auditing
Date:          24/06/2011 10:30:39
Event ID:      4625
Task Category: Logon
Level:         Information
Keywords:      Audit Failure
User:          N/A
Computer:     server1.lab.test
Description:
An account failed to log on.

Subject:
    Security ID:        LOCAL SERVICE
    Account Name:        LOCAL SERVICE
    Account Domain:        NT AUTHORITY
    Logon ID:        0x3e5

Logon Type:            8

Account For Which Logon Failed:
    Security ID:        NULL SID
    Account Name:        WDeployConfigWriter
    Account Domain:        lab.test

Failure Information:
    Failure Reason:        Unknown user name or bad password.
    Status:            0xc000006d
    Sub Status:        0xc000006a

Process Information:
    Caller Process ID:    0x1f44
    Caller Process Name:    C:\Windows\System32\inetsrv\WMSvc.exe

 

The user wants to repair install or uninstall and reinstall the application to “get a quick fix” but we do not to give in and keep trouble shooting. It’s better to learn what the cause really is and how to fix it instead of relying on wishful reinstalling.

So where is the thing that runs under that account. We start a quick search in the registry and on the file system for the  account name just in case it’s configured in the registry or a configuration file and let it run while we keep investigating.  We also send  a tweet in to the universe, as perhaps some one out there  knows this and can help out. We search the internet for Web Deploy 2.0 and WDeployConfigWriter. This results in very few hits, hmmm, interesting  … . One of them is http://blogs.iis.net/msdeploy/archive/2011/04/05/announcing-web-deploy-2-0-refresh.aspx

Where we learn a few things, the most important is the one line from that blog post I formatted in bold and red from the blog snippet right below. I also enlarged the picture from the blog post to make it readable where you can find in IIS  what we learned here:

Notice that Web Deploy setup created two new local user accounts:

- WDeployConfigWriter, which has Write permissions to the IIS server’s applicationHost.config. This is used by delegation rules for createApp, appPoolNetFx and appPoolPipelineMode.

I’ve included the entire block of text from where this was taken below.

1. Easier setup for non-administrator deployments on IIS7

One of the common requests from our users was to make it easier to setup Web Deploy so non-administrators can publish to their sites. Typically, you will need to do this if you are running a shared hosting environment or if you are administering a build machine and you do not want users to have admin access.

If you launch the Web Deploy installer and choose “Custom”, you will notice a new option, “Configure for Non-administrator Deployments”:

clip_image001

If you choose this option, Web Deploy will automatically create Management Service Delegation rules for the following providers, as well as user the accounts needed for providers like createApp and recycleApp that need elevated privileges.

These are the rules you will have in the Management Service Delegation UI in IIS Manager after you install this component:

Notice that Web Deploy setup created two new local user accounts:

- WDeployConfigWriter, which has Write permissions to the IIS server’s applicationHost.config. This is used by delegation rules for createApp, appPoolNetFx and appPoolPipelineMode.

- WDeployAdmin, which is an administrator. This is used by delegation rules for recycleApp.

If you prefer to create these rules by hand, uncheck the component in the installer. We also provide a PowerShell script for creating delegation rules (more on this later in the post) if you prefer that route.

Well armed with this information we go have a look at the Management Service Delegation:

ManagementServiceDelegation

 

Where we indeed find createApp, appPoolNetFx and appPoolPipelineMode:

ManagementServiceDelegationWebdeployconfig

 

So now we take a look a bit what we can configure here and  sure enough, by double clicking on them the Edit Rule form:

ManagementServiceDelegationWebdeployconfigSettings

 

So we click on Edit security credentials and are welcomed by this form:

ManagementServiceDelegationWebdeployconfigSettingsPW1

 

So we enter the account name and the new password we set before (remember to do this for both providers):

ManagementServiceDelegationWebdeployconfigSettingsPW2

 

Guess what, end user happy, things are working again. Jay! From service down report to helpdesk to fully operational again in less than an hour with a technology new to the service desk. Well done young, eager, smart and upward mobile IT Pro Winking smile with lessons learned.

How did this happen and did they end up with this funky configuration (expiring password of an account that no one knows where it is used for and where configured)? Aha, operational control => know the configuration of what you use and know why it is configured that way and where it’s configured. Is it a mistake/assumption in the installer that the accounts WDeployConfigWriter and WDeployAdmin have their passwords set to expired and can be changed by the user or did somebody mess with them after the install? Well I did the test by setting it up on a test server and found that they are indeed installed with their passwords set to expire and that the password can be changed by the user. It assumes that the person doing the install knows and realizes the implications. I’m not saying either setting is wrong but you should know why, when and where. There is no documentation on this as far as we could find right now and perhaps the installer should mention the benefits/risks of both types of configuration and ask what to choose. This, together with better documentation, could help prevent this issue. As always, no guarantees given Winking smile 

Overall lesson: don’t assume things, trust but verify …

KB Article 2522766 & KB Article 2135160 Published Today

At this moment in time I don’t have any more Hyper-V clusters to support that are below Windows Server 2008 R2 SP1. That’s good as I only have one list of patches to keep up to date for my own use. As for you guys still taking care of Windows 2008 R2 RTM Hyper-V cluster you might want to take a look at KN article 2135160 FIX: "0x0000009E" Stop error when you host Hyper-V virtual machines in a Windows Server 2008 R2-based failover cluster that was released today. The issue however is (yet again) an underlying C-State issue that already has been fixed in relation to another issue published as KB article 983460 Startup takes a long time on a Windows 7 or Windows Server 2008 R2-based computer that has an Intel Nehalem-EX CPU installed.

And for both Windows Server 2008 R2 RTM and SP1 you might take a look at an MPIO issue that was also published today (you are running Hyper-V on a cluster and your are using MPIO for redundant storage access I bet) KB article 2522766 The MPIO driver fails over all paths incorrectly when a transient single failure occurs in Windows Server 2008 or in Windows Server 2008 R2

It’s time I add a page to this blog for all the fixes related to Hyper-V and Failover Clustering with Windows Server 2008 R2 SP1 for my own reference Smile

Exchange 2010 SP1 DAG & Unified Messaging Now Supports Host Based High Availability & Live Migration!

Well due to rather nice virtualization support for Lync and the fact that Denali (SQL Server vNext) does support DAG like functionality with Live Migration and host based clustering, it was about time for Exchange 2010 to catch up. And when we read the white paper  Best Practices for Virtualizing Exchange Server 2010 with Windows Server® 2008 R2 Hyper V™ that moment has finally arrived. I have to thank Michel de Rooij at  for bringing this to our attention http://eightwone.com/2011/05/14/exchange-2010-sp1-live-migration-supported/. So now we have the best features in virtualization at our disposal and that simply rocks. We read:

“Exchange server virtual machines, including Exchange Mailbox virtual machines that are part of a Database Availability Group (DAG), can be combined with host-based failover clustering and migration technology as long as the virtual machines are configured such that they will not save and restore state on disk when moved or taken offline. All failover activity must result in a cold start when the virtual machine is activated on the target node. All planned migration must either result in shut down and a cold start or an online migration that utilizes a technology such as Hyper-V live migration.”

“Microsoft Exchange Server 2010 SP1 supports virtualization of the Unified Messaging role when it is installed on the 64-bit edition of Windows Server 2008 R2. Unified Messaging must be the only Exchange role in the virtual machine. Other Exchange roles (Client Access, Edge Transport, Hub Transport, Mailbox) are not supported on the same virtual machine as Unified Messaging. The virtualized machine configuration running Unified Messaging must have at least 4 CPU cores, and at least 16 GB of memory.”

And it is NOT ONLY for Hyper-V, look at the Exchange Team blog here “The updated support guidance applies to any hardware virtualization vendor participating in the Windows Server Virtualization Validation Program (SVVP).’” Nice!

Anyone who’s at TechEd USA 2011 in Atlanta should attend EXL306 for more details. Huge requirements yes, but the same goes for physical servers. That’s how they get the performance gains needed, it’s done by lowering IO by using large amounts of RAM.

Think about the above statement, we now have support for host clustering with live migration, possibly together with technology like for example Melio (SanBolic) on the software side or Live Volume (Compellent) on the storage side to protect against SAN Failure (local or remote) and combined with DAG high availability for the databases in Exchange 2010 (which can be multi site) this becomes a very resilient package. So to come back to my other post on a brighter future for public folders, if they can sort out this red headed stepchild of the Exchange portfolio they have covered all their bases and have a great platform with the option of making it better, easier and cheaper to implement, operate & use. No one will argue with that.

I know some people will say all this is overkill, to complex, to much or to expensive. I call it having options. When the S* hits the fan and you’re “in the fight of your life” wading your way through one or multiple IT disasters to keep that mail flow up an running it is good to have multiple options. Options mean you can get the job done using creativity and tools. If you have only one tool and one option Murphy will catch up with you. Actually this is one of my most heard shout outs to the team “give me options” when problems arise. But at what cost do these options come? That is up for the business and you to decide. We’re getting very robust options in Exchange that can be leveraged with other technologies for high availability that have become more and more main stream. This means none of all this needs to be bought and implemented just for Exchange. They are already in place. Unless your IT “strategy” the last 10 years was run Windows 2000 & Exchange 2000 until the servers fall apart and we don’t have any more spares available on e-bay before we consider moving along.

Déjà vu Bug: The network connection of a running Hyper-V virtual machine may be lost under heavy outgoing network traffic on a computer that is running Windows Server 2008 R2 SP1

Anyone who’s been doing virtualization with Hyper-V on Windows 2008 R2 has a good change of having seen the issue described in http://support.microsoft.com/kb/974909/en-us

You install the Hyper-V role on a computer that is running Windows Server 2008 R2.

  • You run a virtual machine on the computer.
  • You use a network adapter on the virtual machine to access a network.
  • You establish many concurrent network connections, or there is heavy outgoing network traffic.

In this scenario, the network connection on the virtual machine may be lost. Additionally, the network adapter is disabled.
Note You have to restart the virtual machine to recover from this issue.

We’ve seen this one on VM’s that have indeed a lot of outgoing traffic.  In our environment the situation looks like this:

  • You can access the VM with Hyper-V Manager or SCVMM but not via RDP as all Network connectivity is lost.  The status the  guest NIS is always “Enabled” but there is no traffic/connectivity
  • You can try to disable the NIC but this tales a  very long time and when you try to enable it again this never succeeds. Disconnecting the NIC form the virtual network and connecting it again doesn’t help either.
  • You need to shut down the host but this takes an extremely long time, so long you really can’t afford to wait if it ever succeeds. It seems to hang at shutting down with a “non whirling whirly”.  So finally you’ll power off the VM and start it up again. Apart from entries related to having not connectivity the event logs are “clean” and there is no indication as to what happened.

Well this exact same issue is back with Windows 2008 R2 SP1. That’s the bad news. The good news is there is a hotfix for it already so you can fix it. You can read up on this issue in Knowledge Base article 2263829  and request the hotfix here. Instructions to get the hotfix are in there as well as a reference to the previous fixes for Windows 2008 R2 RTM.

Consider the following scenario:

  • You install the Hyper-V role on a computer that is running Windows Server 2008 R2 Service Pack 1 (SP1).
  • You run a virtual machine on the computer.
  • You use a network adapter on the virtual machine to access a network.
  • You establish many concurrent network connections. Or, there is heavy outgoing network traffic.

In this scenario, the network connection on the virtual machine may be lost. Additionally, the network adapter may be disabled.
Notes

  • You must restart the virtual machine to recover from this issue.
  • This issue can also occur on versions of Windows Server 2008 R2 that do not have SP1 installed. To resolve the issue, apply the hotfix that is described in one of the following Microsoft Knowledge Base articles:

    974909 (http://support.microsoft.com/kb/974909/ ) The network connection of a running Hyper-V virtual machine is lost under heavy outgoing network traffic on a Windows Server 2008 R2-based computer
    2264080 (http://support.microsoft.com/kb/2264080/ ) An update rollup package for the Hyper-V role in Windows Server 2008 R2: August 24, 2010

Oh yeah, people often seem confused  as to where to install the hotfix. Does it go on the Hyper-V hosts or and/or on the guest?  It’s a hyper visor bug in Hyper-V so it goes on the hosts. Have a nice weekend.