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.

HOWTO Fix vCenter 4 search not working

First, reset Web Service in vCenter.

Then if it still doesn't work, on the vSphere clien (not verified nor tested)t:

1. Click Plug-in -> manage Plug-ins
2. Right click Hardware Status plugin and select Disable
3. Close and re-open vSphere client.
4. Click Plug-in -> manage Plug-ins
5. Right click Hardware Status plugin and select Enable

(Solution from one of my colleagues. Am not sure if this step is correct.. What does "Hardware Status" plugin have to do with search?)

If steps for client are wrong, welcome corrections.

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!

Tracing source of IP conflict

Look for event id 4199, source Tcpip