Advantages of using VMware PVSCSI interface vs LSI SAS and it's caveats

Updated (again) 1330hrs:
Appended some other interesting information from the discussion resulting from that Facebook post.
Thanks guys!

LSI SAS by defaults supports only queue depth of 25. (needs further confirmation) vs PVSCSI.

Original Post:-

While there are host OS (HOS) and guest OS (GOS) optimizations that will increase performance, there are caveats to note.

My recommendation would be to follow VMwares' best practice (gleaned from various forum posts and blogs - not sure if there are any such official articles/KBs) and do not configure your OS disk/partition with PVSCSI especially in a production environment where you may have a few other VMware administrators.

However, for a controlled test environment like home labs, by all means try it. All my home lab VMs are running PVSCSI on OS disks too. ;)

The details of why "don't do that" follow:

This is a reply to a post on Facebook's VMUG ASEAN to a question on how to configure PVSCSI replacement interface.

(Don't know if this hotlink to the post on VMUG  ASEAN will work. If anyone knows a sure-fire way to link Facebook posts let me know in the comments below :D )

Here's my 2 cents.  I did some deep dive research on PVSCSI and there are caveats. Some OS may have issues with it. Particularly VMware View. For PVSCSI to work, VMtools has to be installed and functional. There may be some situations where when you update or lose the VMtools you might lose connectivity to the disks connected using the PVSCSI device. I had considered using PVSCSI as the OS boot interface (after switching the vNIC using the article Lalit Sharma mentioned. However, if you get into a situation where you need to boot the OS (Windows in this case, Linux I don't have enough experience) to repair the OS, you will have to reconfigure the interface back to LSI or the default Windows boot media won't be able to access the OS disk. So take these things into consideration. Anyhow for my home lab, everything is on PVSCSI. Just it may not be wise in production environment especially if you have other vSphere admins that may not be as familiar.

Appends:-

Roshan Jha: Posted a recent VMware blog article (which I did not see earlier). 
It's VSAN related but relevant.

Which vSCSI controller should I choose for performance?  - Mark Achtemichuk

Kasim Hansia: "LSI only supports 32 queue depth and PVSCSI queue depth default values are 64 (device) and 254 (adapter). You can increase PVSCSI queue depths to 256 (device) and 1024 (adapter) inside a Windows or Linux Virtual Machine. "

Tan Wee Kiong - thanks for the correction of the initial assumption and the following KB article:

"Large-scale workloads with intensive I/O patterns might require queue depths significantly greater than Paravirtual SCSI default values (2053145)"

"The large-scale workloads with intensive I/O patterns require adapter queue depths greater than the Paravirtual SCSI (PVSCSI) default values. Current PVSCSI queue depth default values are 64 (for device) and 254 (for adapter). You can increase PVSCSI queue depths to 256 (for device) and 1024 (for adapter) inside a Windows virtual machine or Linux Virtual Machine."

Note that the article has made a distinction between a "device" and the "adapter".

Fix - Citrix XenAppWeb.msi v11.0.0.5357 problem with IE9

Hopefully, this will save someone lots of hair-pulling.

Symptoms:
IE9 crash on connection, IE9 goes into install loop upon connection with web interface.

Other error messages during debug process:
"The configuration manager cannot be initialized"

Offending client version information:
11.0.0.5357 - GUID {388C130B-0079-46B4-A0D5-DC2DD7A89A7B}

Solution:
This is a known problem see Citrix KB CTX126653 and CTX129082


Download client Online Plug-in 12.3, Release Date: 4/16/2012


Other useful KBs:

Manually removing files that might remain after uninstalling the Citrix receiver for Windows.

http://support.citrix.com/article/CTX325140


This article has a table with GUIDs that might be useful:
http://support.citrix.com/article/CTX121917

Windows 2003 - Enable OS firewall to allow exceptions by IP(s) and IP range(s).

There is no elegant way to do this on Windows 2003 Server.

The following will add TCP ports 5500 to 5700 one at a time - run at the command line.

"FOR /L %I IN (5500,1,5700) DO netsh firewall add portopening TCP %I "Passive FTP"%I"

The inelegant way is to add port range, you can use the GUI to add that range to a defined port then export that registry entry and make changes to that .reg file and import it back.

Will update details at later time.

Kindle for PC - This book could not be opened

What worked for me. 

Start Kindle for PC, on menubar click on Tools, click Options, select/highlight Registration, click on Deregister.

Re-register by signing in again. Fixed!

Shadowing a RDP session

In short:
1. RDP to the server (it must be on the same server afaik) with the RDP session you want to shadow
2. Open command prompt
3. Type "shadow

Reference:
http://support.microsoft.com/kb/320191

Tracing source of IP conflict

Look for event id 4199, source Tcpip

HOWTO: Locating Global Catalog (GC) Servers in Windows Domain

nltest /dsgetdc: /GC

or

repadmin.exe /options * and use IS_GC for current domain options

To remove unused plug-in from vCenter use Managed Object Reference

Found at http://vcenterservername/mob

Logon with vSphere credentials;

1. Click on content, then
2. Extension manager
3. Find the plug-in which needs to be removed; for example, look for extensionList["VirtualCenter"], the parameter you need is just VirtualCenter
4. Click UnregisterExtension, in the VALUE field, enter the name of the plug-in you wish (in this example it's VirtualCenter
5. Click on Invoke Method (to remove plug-in

vCenter and SQL 2008 SP1 on Windows 2008 R2

1.  vCenter won't install on the Web Edition.
2. You can install SQL2008 on 2008 R2, just have to disable all services until SP1 has been applied.
3. When creating the ODBC connections, use "%systemdrive%\Windows\SysWoW64\Odbcad32.exe" and not the ODBC from Administrative Tools section.

BEFORE, installing vCenter Server, do:

1.       Start -> Administrative Tools -> Server Manager.

2.       From the left pane, select “Features”

3.       On the right hand pane, click “Add Features”

4.       Expand .NET Framework 3.5.1 Features

5.       Select only .NET Framework 3.5.1 (do not select WCF Activation as it will install IIS which conflicts with Apache Tomcat, which of course vCenter will install).

vCenter Server should now install without any issues.

Reconnect child domain to AD forest after tombstone period without demoting child domain DCs

Frankly information on how to fix this problem IS available. It's just that Microsoft's support site contains KB articles that haven't been fully updated.

See this article: Orphaned child domain controller information may not be replicated to other Windows 2000 Server-based domain controllers

To resolve this issue, you must create a replication link, and you must enable one-way authentication instead of two-way authentication. To do this, follow these steps:

1. On a domain controller in the root domain, add the Replicator Allow SPN Fallback registry value. To do this, follow these steps.
   
   Note Perform steps 1 through 6 on this same domain controller.
   
   1. Click Start, click Run, type regedit, and then click OK.
   2. Locate and then click the following registry subkey:
      
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Parameters
   3. On the Edit menu, point to New, and then click DWORD Value.
   4. Type Replicator Allow SPN Fallback, and then press ENTER.
   5. Double-click Replicator Allow SPN Fallback in the right-pane, type 1 in the Value data box, and then click OK.
   6. Restart the domain controller.
2. At a command prompt, type the following:
   
   repadmin /optionsfully_qualified_domain_name_(FQDN)_of_the_root_domain_controller+DISABLE_NTDSCONN_XLATE
   
   
   Note The Repadmin.exe tool is located in the Windows 2000 Support Tools. 
   
   For additional information about how to install the Windows 2000 Support Tools, click the following article number to view the article in the Microsoft Knowledge Base:
   
   301423  How to install the Windows 2000 support tools to a Windows 2000 Server-based computer
3. At a command prompt, type the following:
   
   repadmin /add CN=Configuration,DC=Domain_Name,DC=Domain_NameFQDN_of_the_root_domain_controller FQDN_of_the_child_domain_controller
4. At a command prompt, type repadmin /showreps. A successful incoming connection should be displayed for the configuration naming context from the child domain controller.
5. At a command prompt, type the following:
   
   repadmin /options FQDN_of_the_root_domain_controller -DISABLE_NTDSCONN_XLATE
6. Remove the Replicator Allow SPN Fallback registry entry. To do this, follow these steps:
   
   1. Click Start, click Run, type regedit, and then click OK.
   2. Locate and then click the following registry subkey:
      
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Parameters
   3. Right-click Replicator Allow SPN Fallback, click Delete, and then click OK.
7. Force replication between all domain controllers in the root domain. To do this, follow these steps:
   
   1. On a domain controller in the root domain, click Start, point to Programs, point toAdministrative Tools, and then click Active Directory Sites and Services.
   2. Expand Sites, expand Servers, expand your Server_Name folder, and then click NTDS Settings.
   3. If there are other domain controllers in your environment to replicate, they will be listed in the right pane. Right-click the first domain controller in the list, click All Tasks, and then click Check Replication Topology to start the Knowledge Consistency Checker (KCC). 
      
      An incoming connection object from one or more of the child domain controllers is displayed. You may have to update the display by pressing F5.
      
      Note You must perform this step for each domain controller in the root domain.
8. Allow replication to occur throughout the forest. Then, run the repadmin /showreps command on the root domain controller and on the child domain controllers. This step makes sure that Active Directory directory service replication is successful. 
   
   Note The "Replication Allow SPN Fallback" registry entry enables the Active Directory to use one-way authentication if two-way authentication cannot be performed because of a failure to resolve a Service Principle Name (SPN) to a computer account.

@ARK-DS

Problem is almost resolved.  Been talking to Microsoft these last two weeks - we are at the last stage of monitoring replication and cleaning up.

And yes, you are right about KB http://support.microsoft.com/kb/887430. It's the first step required to rejoin the orphaned domain to parent. Unfortunately, I didn't get confirmation that this would work with Windows 2008 servers and in Windows 2003 Forest/Domain level installations - if I had, it would have saved a call to Microsoft. :-)  AND Microsoft's KB article was updated (APPLIES TO doesn't mention anything other than Windows 2000 Servers!!) See attached image kb887430.jpg

However, the whole process isn't as simple and involves many steps.

OK people, this is for the benefit of the masses.

From watching Microsoft troubleshoot the problem, besides the SOPs they ask you to do, (MPSReport, Network analyser captures, etc), these are the steps and things to take note of if you have a situation such as this.

1. You need to run the commands on the PDC.
2. You need to double-check using regedit even after using the "repadmin /regkey " - If you don't do that, although the command returns successful execution, the key might still be there.

www.experts-exchange.com/Software/Server_Software/File_Servers/Active_Directory/Q_25306989.html#a30815303

WSUS 3.0 SP2 on Windows Web Server 2008 R2

To install IIS 7.0 on Windows Server 2008

1. Start the Server Manager (click Start, click Run, and then type CompMgmtLauncher).
2. In the tree view, select Roles, then in the Roles pane click Add Roles.
3. In the Add Roles Wizard, click Select Server Roles, select the Web Service (IIS) check box, click Next, and then click Next again.
   At this time you may see a message box Add features required for Web Server (IIS)? Click Add Required Features.
4. In the Select Role Services window, make sure that the following services are selected:
   • Common HTTP Features (including Static Content)
   • ASP.NET, ISAPI Extensions, and ISAPI Features (under Application Development)
   • Windows Authentication (under Security)
   • IIS Metabase Compatibility (under Management Tools, expand IIS 6 Management Compatibility)
5. Click Next, and then review your selections.
6. Click Install.