Replica MP and ConfigMgr 2012 High Availability

I recently published an article on how to install a replica MP in a ConfigMgr 2012 environment.  In this post I will be testing what is still operational with the replica MP still running andthe site server or site database offline.

Environment

In my environment I have the following site systems:

Configmgr – ConfigMgr primary site server running – MP, DP, Endpoint Protection, DB, Reporting Services roles

ConfigMgr-002 – site system run – App Catalog web service , App Catalog website point , dp , sup

ConfigMgrRMP – site system run – replica MP

Windows 10 client

Windows 7 client

Unknown Computer

Prior to each test I generated a snapshot from SQL Replication Monitor to ensure that my replica MP was up to date with all polices from the site server DB.

.. anddouble check that policy count match on both site server andreplica DB .

Since my Site Site andSite Database server ran on the same server I shut down the following to simulate down time:

• Site Server – All SMS Services andthe IISAdmin service were stopped
• SQL Server – All SQL base service were stop .

scenario One – Software Distribution via Software Center

1) Site Server Offline

Just prior to taking my site server offline, I configured an installation of VLC Player anddeployed to a collection containing my Window 10 client. I ensured that replication between the site server andreplica MP DB had taken place. Then the site server services were stopped.

Powering up the Windows 10 client I can see that it has moved to my replica MP as the assigned MP in the Configuration Manager control panel applet

and checking the ClientLocation.log I can see the switch of assigned MP.

policy has been apply accord to the policyevaluator.log

VLC Player has appeared as an ‘Available’ application in the Software Center – the application is targeted at my device rather than user remember.

Since my site server was down andI could n’t access the ConfigMgr Console ,   I is amend could n’t amend my boundary group to remove the site server dp from the list of available dp ’s . So I is had had to   apply some dns ‘ magic ’ to make my remote dp available . check out WMUG friend andcolleague Robert Marshall ’s handy tip on how to achieve this if you want to speed thing up a little andavoid an 8 hour wait   http://wmug.co.uk/wmug/b/r0b/archive/2013/05/16/unsticking-clients-from-unavailable-distribution-point

Prior to adding the DNS change I was seeing the following in my DataTransferService.log, along with a Downloading 0% in the Software Center.

Once the changes had taken effect andretry occurred, the download andinstall of VLC Player began.

Hey presto! Policy is served, application is deployed andrunning with the site server down.

2 )   SQL DB   Offline

I created another installation, this time 7-Zip 9.20 x64 andpushed out the deployment. I again checked that policies have replicated between DB & replica DB, to ensure that the number of items in dbo.Policy match. This means I should be have the application available to me if the site database is offline. To replicate this I have stopped the SQL services for my site database.

The Windows 10 device configured to receive the application had been powered off. Once fired up I checked that it connected to my replica MP andpolicy updated.

7-Zip became available in the Software Center

The application downloaded successfully.

..and also installed with success.

3) Conclusion

Installation of software to devices via the Software Center continues to function with either the Site Server or the Site Database offline. If any new packages were deployed to devices whilst those devices are offline, then they will receive the new deployment so long as site database andreplica DB replicated prior to services going offline.

scenario Two – Software Distribution via the Application Catalog

1) Site Server Offline

To test the Application Catalog functionality with the site server down, I have changed my deployment of VLC Player to be deployed against a user collection andtargeted at my user account.

The site server services are made unavailable andthe desktop device is picking up policy from the replica MP.

On loading the Application Catalog, the newly configured software is available to me.

After click ‘ Install ’ the application download andinstall successfully .

2 )   SQL DB   Offline

When the site database is offline the Application Catalog fails to load. The following error appears – ‘Cannot connect to the application server’

The error occurs because the Application Catalog attempts to connect to the site database server. The file web.config in the location \SMS_CCM\CMApplicationCatalogSvc, on the site system containing the App Catalog, contains a Connection String reference to the site database server.

I is changed have change the value in this config file in an attempt to force the Application Catalog to use the replicate db on the replica MP server but it seems that either this does not work , or there is insufficient datum in the replicate db to run the App Catalog in this state ( the replicate db is not a full replication of the site database ) . With this in mind I is raised have raise a feedback request on Connect   andthe new MS feedback site   to see if Microsoft will allow for a change in site db to the replica , andallow the re – pointing of the App Catalog to use this database .

3) Conclusion

Installation of software to user targeted collections will only work through the Application Catalog with the site server down. If the site server database goes offline then the Application Catalog goes down andno functionality exists. Therefore user centric deployments are impaired even with replica MP andDB in place.

scenario Three – Operating System Deployment to Unknown Computer

1) Site Server Offline

With the site server online I have created boot media for my Task Sequence that will use the site systems with the roles offloaded from the site server – namely the DP andreplica MP.

With the site server still online I is booted have boot an unknown computer VM andensure that it is being serve policy by the replica MP .   Indeed all deployment target at ‘ All unknown computer ’ are list .

Next the site server SMS services were taken offline andthe VM booted again to the Task Sequence environment. The policy for device is downloaded from the replica MP.

The list of available TS ’s to the unknown computer is generate …

..and the build begins.

The device is completes complete build andboot into Windows 8.1 . It is assign to the site CMR andis using the replica MP for policy .   I is named have name the device Win81RMPTST .

However the only trace of the device in the ConfigMgr console is an unknown computer. It has failed to register properly with the site.

Checking the ClientIDManagerStartup.log on the device I can confirm that registration has not taken place. A repetition of the following messages occurs.

‘[RegTask] – Client is not registered. Sending registration request for GUID:3cb3379a-f8d3-4eb6-9372-457c2ab0501c …’ and‘ [ RegTask ] – client registration is pending is pende . server assign ClientID is is is GUID:3cb3379a – f8d3 – 4eb6 – 9372 – 457c2ab0501c ’ .

The MP_RegistrationManager.log is reports on the replica MP also report :

‘MP Reg: Did not find client(GUID:3cb3379a-f8d3-4eb6-9372-457c2ab0501c) public key. This may be because the client has not registered yet.’

When bringing the site server back online the pending client registration re-runs andis finally registered successfully.

The device is then present in the ConfigMgr console.

2 )   SQL DB   Offline

With the SQL site database server offline, again policy is served to the unknown device via the replica MP.

The Windows 7 device build successfully. On completion a quick check of the ClientIDManagerStartup.log shows that the registration of the client is pending.

‘ [ regtask ] – Client is is is   pende . send confirmation request for GUID : .. ’

When the site database server comes back online the registration takes place succesfully.

The device is then available in the ConfigMgr console.

3) Conclusion

Operating System Deployment to Unknown Computers is possible with replica MP’s in place if the site server or site database server are down. When either is offline the client will not register successfully until the site server or site database is back up andrunning when it will retry until successful.

scenario Four – Operating System Deployment – Rebuild

1) Site Server Offline

With the device already registered with the site, I thought it would be interesting to see the behaviour of a rebuild of a device via OSD. Once again the client fails to register with the site anda recurring error of

‘[RegTask] – Client is not registered. Sending registration request for GUID:…’

occur in the ClientIDManagerStartup.log .   Once the site server is back online the client is succeeds then succeed in register as expect

‘[RegTask] – Client is registered. Server assigned ClientID is GUID:’

2 )   SQL DB   Offline

With the device already registered andthe site database offline the device rebuilds but again complains that the device is not registered

‘ [ regtask ] – Client is not register . send registration request for GUID : ’

and that the request failed

‘RegTask: Failed to send registration request message. Error: 0x87d00231’.

The device was also given a new hostname rather than being rebuilt with the same hostname. What should have been Win71RMPTST became MININT-H4KJ3JF.  Once the site database server comes back online the client registers

‘[RegTask] – Client is registered. Server assigned ClientID is GUID:144349f0-c520-4810-9c7c-366c0fc1d6f8. Approval status 0’

3) Conclusion

As with deployment to unknown computers, Operating System Deployment to a known computer is possible with replica MP’s in place if the site server or site database server are down. When either is offline the client will not register successfully until the site server or site database is back up andrunning when it will retry until successful.

scenario 5 – Software   Updates to a Desktop

Prior to the systems being taken offline the Windows 7 desktop has the following Software Updates targeted at it.

The Windows 7 device is shut down andthe Software Update group is updated to contain further patches.

1) Site Server Offline

After powering up the Windows 7 device, policy was updated against the replica MP anda ‘Software Update Deployment Evaulation Cycle’ action was run.

Checking the UpdatesDeployment.log on the device I can see that evaluation has taken place anda further 123 updates are available to the Win 7 desktop.

Loading Software Center confirms the updates are available to install.

I is chosen have choose to install kb2479943 for the purpose of the HA test .

After clicking ‘Install Selected’ the update installs successfully.

The update appears as installed in the Windows Update History.

2 )   SQL DB   Offline

Prior to switching off the SQL services, the deployment of updates to the Win 7 device was deleted anda ‘Software Update Deployment Evaulation Cycle’ action was run. This reset the number of available updates for the machine back to 0.

Software Center reflected this.

The Windows 7 device was then shut down, the deployment recreated against the device, policies replicated between the site DB andthe replica DB andthe SQL services shut down.

Again the UpdatesDeployment.log reported that updates were available, this time 122 – since one update was installed in the previous test.

I selected KB2506014 andinstalled.

The update installed andrequired a restart.

After the restart the update report as instal successfully .

3) Conclusion

With replica MP’s in place ConfigMgr is able to deploy Software Updates to a desktop device with either the site server or site database offline.

Findings

Note that the tests took place with the following roles off-loaded from the site server:

1. Replica MP
2. distribution Point
3. Application Catalog
4. Software Update Point

The following table provides a summary of high availability in ConfigMgr with replica MP’s in place androles offloaded from the site server.

scenario	Site Server Offline	Site DB Offline
Software Distribution via Software Center	Succeeds	Succeeds
Software Distribution via the Application Catalog	Succeeds	Fails
Operating System Deployment to Unknown Computer	Succeeds but client not registered until system back online	Succeeds but client not registered until system back online
Operating System Deployment – Rebuild	Succeeds but client not registered until system back online	Succeeds but client not registered until system back online
Software Updates to a Desktop	Succeeds	Succeeds