I'm just using this as a "notepad" of sorts.
Just took over a site with many downstream WSUS and trying fix the existing issues.
Don't expect a complete solution here!
This will be updated as I go along but then again, maybe not!
WSUS Tips & Tricks:
https://community.spiceworks.com/topic/1677852-how-to-administer-wsus
No update files downloaded in WSUS Content folder:
http://clintboessen.blogspot.sg/2013/09/windows-server-2012-wsus-server-not.html
https://thwack.solarwinds.com/thread/54281
https://social.technet.microsoft.com/Forums/windowsserver/en-US/97e1170e-0506-4cf1-918c-6d472b352ff6/wsus-not-downloading-the-updates?forum=winserverwsus
https://serverfault.com/questions/754267/wsus-upstream-server-is-not-showing-current-downstream-server-status
SQL Script to clean WSUS:
https://community.spiceworks.com/scripts/show/2998-adamj-clean-wsus
WSUS Error Codes:
8024401F - Equivalent to a HTTP 500 error; IIS had an internal server error while processing download request; check your default ports on WSUS if they match GPO settings. If that's not the issue see this:- http://kaustubhghanekar.blogspot.sg/2011/05/advanced-wsus-troubleshooting-for-error.html
WSUS Error Codes Database:
http://inetexplorer.mvps.org/archive/windows_update_codes.htm
Script for WSUS cleanup:
https://docs.microsoft.com/en-us/powershell/module/wsus/invoke-wsusservercleanup?view=win10-ps
Troubleshooting:
IIS Logs C:\inetpub\logs\LogFiles
Alternative method of deploying drivers from WSUS:
https://decentsecurity.com/drivers-through-wsus/
Downloading Drivers using WSUS:
http://www.runonazure.com/downloading-drivers-into-wsus-bad-idea/
https://blogs.technet.microsoft.com/sus/2008/08/20/a-large-number-of-driver-updates-showing-up-in-wsus/
http://www.runonazure.com/downloading-drivers-into-wsus-bad-idea/
Deleting WID:
https://systemspecialist.net/2013/05/15/move-or-delete-a-wsus-4-windows-internal-database-wid-on-windows-server-2012/
Just happy sharing nuggets. My Personal Wiki. Blog contains mostly technical stuff which may be of interest to some but mostly useful for me.
Wednesday, April 26, 2017
Monday, January 30, 2017
Windows 10 Insider Preview update issues from build 15007 to 15019; this probably will apply to some situations outside this scenario.
For those of you on Windows Insider Preview 10 build 15007 trying to move up to build 15019, go to services, disable "Delivery Optimization" service, reboot and retry. I used the Resource Manager to monitor network connections out and notice that after disabling the "Delivery Optimization" service, "svchost.exe (netsvcs)", started receiving incoming data. After the download for 15019 was completed, I set the service back to Automatic but did not start it. This is just in case having this in disabled state will mess up future installations. My setup is a VM on VMware Workstation so YMMV. Good luck guys. :)
I've placed the screenshots of the process in a public post on Facebook for reference:
https://www.facebook.com/midus/posts/10154325183861724
I've placed the screenshots of the process in a public post on Facebook for reference:
https://www.facebook.com/midus/posts/10154325183861724
Friday, October 14, 2016
Clearing space on C: drive on Windows 7
It's been a REALLY long time since I've blogged anything.
Anyhow, I've been with my current company for almost five years and have been using the same notebook running on Windows 7 for all these years.
Yes, they have given me a new notebook after 3 years, but I've stuck with the current one for reasons which shall not be covered in this article. :P
Basically, I ran out of space on my C: drive. I had only 10.5GB left out of 108GB.
Here's how a quick and dirty note on how to clear space besides using "Disk Cleanup".
DISCLAIMER:
Make sure you have a Systems Image backup in case you FUBAR your machine.
This "note" here is meant for my own future reference.
If you destroy, break, damage, get yourself into hot soup in office because of this, it's your decision and choice. I cannot be held responsible for your choice of actions.
Now that that's been said...
1. Run "PatchCleaner" and MOVE the orphaned/old patch folders to another location. This program can be gotten from "http://download.cnet.com/PatchCleaner/3000-18512_4-76399133.html" - this effectively managed to clear about 11GB of space.
2. Move your Windows Search Index off to another drive. How to do that?
- Open a administrative command prompt
- Run this command line "rundll32.exe shell32.dll,Control_RunDLL srchadmin.dll"
- Click on "Advanced", on next screen, click on "Select New" and choose the folder you want to move the index files to.
- Click "OK" and wait.
Once control returns to the application, you will have more free space on your C: drive. I got back another 11.5GB of space on my C: drive.
Hope the above steps helps. And as usual, YMMV.
Anyhow, I've been with my current company for almost five years and have been using the same notebook running on Windows 7 for all these years.
Yes, they have given me a new notebook after 3 years, but I've stuck with the current one for reasons which shall not be covered in this article. :P
Basically, I ran out of space on my C: drive. I had only 10.5GB left out of 108GB.
Here's how a quick and dirty note on how to clear space besides using "Disk Cleanup".
DISCLAIMER:
Make sure you have a Systems Image backup in case you FUBAR your machine.
This "note" here is meant for my own future reference.
If you destroy, break, damage, get yourself into hot soup in office because of this, it's your decision and choice. I cannot be held responsible for your choice of actions.
Now that that's been said...
1. Run "PatchCleaner" and MOVE the orphaned/old patch folders to another location. This program can be gotten from "http://download.cnet.com/PatchCleaner/3000-18512_4-76399133.html" - this effectively managed to clear about 11GB of space.
2. Move your Windows Search Index off to another drive. How to do that?
- Open a administrative command prompt
- Run this command line "rundll32.exe shell32.dll,Control_RunDLL srchadmin.dll"
- Click on "Advanced", on next screen, click on "Select New" and choose the folder you want to move the index files to.
- Click "OK" and wait.
Once control returns to the application, you will have more free space on your C: drive. I got back another 11.5GB of space on my C: drive.
Hope the above steps helps. And as usual, YMMV.
Saturday, June 20, 2015
A geek's comments (review?) about the Amazon Fire Phone - It's actually pretty good!
I've owned this phone since February. I've been using it as my spare phone at home only. But I've grown to really like this phone. That's possibly because I'm also heavily invested into the Amazon eco-system. :) I've got the Amazon Echo, several kindles (The Kindle HDX 8.9 is my favorite device)
Anyhow, now that SwiftKey and Google Play services are successfully installed on my Amazon Fire Phone, I can honestly say this is the best value phone you can get on the market. For less than 300 bucks, 32GB storage, quad core. It's got good heft and excellent build quality. Anyone wants to get a feel of it? So far all my tech colleagues whom have handled it all like it. Pity Amazon didn't get a fair chance.
Excellent screen, excellent fonts. Excellent sound processing. There is a noticeable difference in audio quality compared to my Xperia Z2 when streaming to a Bluetooth speaker. The sound is warm and fuller. I don't know. I'm just growing to enjoy this phone the more I use it. Am typing this review on this phone right now.
I'm still using the default Amazon UI. The gesture controls grow on you. So much so that I even ended up mistakenly swiping up on my Xperia Z2.
What I don't like: The default keyboard. That's probably because I'm too used to the auto correct and prediction functionality of SwiftKey. I don't use flow. I'm used to back swiping for deleting. I also can't seem to find where the context switching button is. I'm used to quickly switch applications but on the fire phone... Where the hell is that?
Anyhow, now that SwiftKey and Google Play services are successfully installed on my Amazon Fire Phone, I can honestly say this is the best value phone you can get on the market. For less than 300 bucks, 32GB storage, quad core. It's got good heft and excellent build quality. Anyone wants to get a feel of it? So far all my tech colleagues whom have handled it all like it. Pity Amazon didn't get a fair chance.
Excellent screen, excellent fonts. Excellent sound processing. There is a noticeable difference in audio quality compared to my Xperia Z2 when streaming to a Bluetooth speaker. The sound is warm and fuller. I don't know. I'm just growing to enjoy this phone the more I use it. Am typing this review on this phone right now.
I'm still using the default Amazon UI. The gesture controls grow on you. So much so that I even ended up mistakenly swiping up on my Xperia Z2.
What I don't like: The default keyboard. That's probably because I'm too used to the auto correct and prediction functionality of SwiftKey. I don't use flow. I'm used to back swiping for deleting. I also can't seem to find where the context switching button is. I'm used to quickly switch applications but on the fire phone... Where the hell is that?
Tuesday, April 28, 2015
Long live VMFS3! VAAI enabled storage, ESXi 5.x and above, thin VMDK files = Not able to recover unused (null) space.
Basically we still need a VMFS3 datastore as a "AUX" to shrink disks.
This is interesting! Basically, logically, in plain English.. what happens is since the VAAI datamover used is not at the ESXi layer, the storage doesn't know what is on the VMDK and _has-to_ copy everything. There is no chance for ESXi layer to figure out which blocks to drop!
The conditions - ESXi 5.x onwards (VMFS5) + VAAI capable/enabled storage, Thin Provisioned VMs
"...When the source filesystem uses a different blocksize from the destination filesystem, the legacy datamover (FSDM) is used. When the blocksizes of source and destination are equal, the new datamover (FS3DM) is used. FS3DM decides if it will use VAAI or just the software component. In either case, null blocks are not reclaimed"
Thanks to Boon Hong for highlighting this.
http://kb.vmware.com/kb/2004155
This is interesting! Basically, logically, in plain English.. what happens is since the VAAI datamover used is not at the ESXi layer, the storage doesn't know what is on the VMDK and _has-to_ copy everything. There is no chance for ESXi layer to figure out which blocks to drop!
The conditions - ESXi 5.x onwards (VMFS5) + VAAI capable/enabled storage, Thin Provisioned VMs
"...When the source filesystem uses a different blocksize from the destination filesystem, the legacy datamover (FSDM) is used. When the blocksizes of source and destination are equal, the new datamover (FS3DM) is used. FS3DM decides if it will use VAAI or just the software component. In either case, null blocks are not reclaimed"
Thanks to Boon Hong for highlighting this.
http://kb.vmware.com/kb/2004155
Tuesday, February 17, 2015
Temporarily disabling password complexity on hardened CentOS 6.5
Navigate to etc/pam.d
(system-auth is symbolic link to system-auth-ac)
Rename original file:
"mv system-auth-ac system-auth-ac-backup"
Create a new file
"cp system-auth-ac-backup system-auth-ac"
Edit "system-auth-ac"
Look for line that starts with "password required pam_cracklib.so"
Change parameters "minlen=1", "dcredit=0", "ucredit=0", "ocredit=0", "lcredit=0"
Save the file (No reboot is required)
Change password with "passwd"
Revert original file:
"cp system-auth-ac-backup system-auth-ac"
Remove bash history
make sure you're in your "profile" directory
"rm .bash_history" - you will be prompted if you want to delete the file.
Patching CentOS 6.5 on VMware
Just a quick and dirty post for my future reference.
Sometimes, the OS gets confused. Especially if there are additional lines for VMXNET.
When you run "system-config-network", eth0 should show the VMware NIC type, for example "VMXNET3"
Otherwise;
1. Remove the unnecessary lines from /etc/udev/rules.d/70-persistent-net.rules
2. Make sure the MAC address matches matches the ESXi assigned
3. Restart the services "service network restart"
4. "yum clean all" (in case cache is pointing to dead update locations)
4. yum update
Location of network configuration file: (assumption for 1st network adapter)
/etc/sysconfig/network-scripts/ifcfg-eth0
Sometimes, the OS gets confused. Especially if there are additional lines for VMXNET.
When you run "system-config-network", eth0 should show the VMware NIC type, for example "VMXNET3"
Otherwise;
1. Remove the unnecessary lines from /etc/udev/rules.d/70-persistent-net.rules
2. Make sure the MAC address matches matches the ESXi assigned
3. Restart the services "service network restart"
4. "yum clean all" (in case cache is pointing to dead update locations)
4. yum update
Location of network configuration file: (assumption for 1st network adapter)
/etc/sysconfig/network-scripts/ifcfg-eth0
Friday, January 16, 2015
vSphere Web Client Abobe Flash Offline Installer
Just a very quick post for future reference:
Platform to install on: Windows 2008 R2 Server, IE.
See this URL from Adobe Forum:
https://forums.adobe.com/thread/889580
Direct download of IE active-x installer (Version 13 extended support):
http://download.macromedia.com/get/flashplayer/current/licensing/win/install_flash_player_13_active_x.exe
Platform to install on: Windows 2008 R2 Server, IE.
See this URL from Adobe Forum:
https://forums.adobe.com/thread/889580
Direct download of IE active-x installer (Version 13 extended support):
http://download.macromedia.com/get/flashplayer/current/licensing/win/install_flash_player_13_active_x.exe
Wednesday, September 17, 2014
Insomniac Ramblings is now Midus Renaissance.
This is not a technical post.
However I feel that this will be useful for people with problems sleeping.
As I'm no longer having sleep issues, I thought maybe it's time to update the name of this blog.
The "solution" I found in the end for this disorder was through the holistic path.
In short, I finally consulted with a Tradition Chinese doctor and "resetting" my internal flow has allowed me to sleep well at night after years of battling.
I think Insomnia is prevalent among many in our times - it detracts from the overall quality of life and can inadvertently, insidiously affect other aspects of one's life.
As this is an update and not a technical post (yet) I'd like to leave the topic open and hoping maybe someone else can be helped.
Looking forward to robust discussions (if any)
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".
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".
Labels:
adapter queue depth,
caveats,
device queue depth,
disk,
how-to,
howto,
interfaces,
LSI SAS,
optimzations,
PVSCSI,
queue depth,
storage,
tuning,
VM,
VMware,
VMware Tools,
VSAN,
vSphere
Tuesday, July 1, 2014
Disabling many AD user accounts on Windows Server 2003 without powershell
This may or may not help you but it's for my future reference.
My source was from dumping using MAP (Microsoft Assessment and Planning) toolkit using report "ActiveDevicesUsageTracker"
My AD wasn't using the default OU structure
Usable output = "Username" column = samID
Retrieve User-DN on Windows Server 2003
With the samID above, for each name
dsquery user -samid
Disable AD user accounts on Windows Server 2003
dsmod user user-DN -disabled yes
References (just got the important bits):
http://technet.microsoft.com/en-sg/library/cc781527(v=ws.10).aspx
https://kb.bluecoat.com/index?page=content&id=KB4548
Not related but I needed to get the AD group membership of those disabled AD accounts for clean up purposes.
Retrieve by AD user object AD group membership:
dsget user "" -memberof -expand
Reference:
http://social.technet.microsoft.com/wiki/contents/articles/2195.active-directory-dsquery-commands.aspx
My source was from dumping using MAP (Microsoft Assessment and Planning) toolkit using report "ActiveDevicesUsageTracker"
My AD wasn't using the default OU structure
Usable output = "Username" column = samID
Retrieve User-DN on Windows Server 2003
With the samID above, for each name
dsquery user -samid
Disable AD user accounts on Windows Server 2003
dsmod user user-DN -disabled yes
References (just got the important bits):
http://technet.microsoft.com/en-sg/library/cc781527(v=ws.10).aspx
https://kb.bluecoat.com/index?page=content&id=KB4548
Not related but I needed to get the AD group membership of those disabled AD accounts for clean up purposes.
Retrieve by AD user object AD group membership:
dsget user "
Reference:
http://social.technet.microsoft.com/wiki/contents/articles/2195.active-directory-dsquery-commands.aspx
Tuesday, June 24, 2014
VMware vSphere Snapshots (draft-WIP)
This post aims to condense and place into a single page important information with regards to snapshots, svmotion (snapshots are used), cloning (snapshots used there too!) and some general issues and questions which I've encountered in my working environment. (quiescing errors, during Avamar backup, during cloning of "hardened" windows GOS)
I started out looking for supporting articles but ended up going in and out of KBs and losing track of what belongs to what, where belongs to where. Hence this post. It's mostly my notes of what I think will be useful and important while troughing through the maze of KB articles.
Start here (Understanding how Snapshots work on different versions of ESX/ESXi)
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1015180

When performing Storage vMotion
http://blogs.vmware.com/vsphere/2011/09/storage-vmotion-storage-drs-virtual-machine-snapshots.html
"It should also be noted that if you do a Storage vMotion of a VM with snapshots and the VM has the workingDir parameter set, theworkingDir setting will be removed from the .vmx & the .vmsn snapshot data file will be moved to the home folder of the VM on the destination datastore. You do get a warning in the migration wizard about this"
"Therefore, if you use the snapshot.redoNotWithParent = "TRUE" parameter, you should refrain from doing Storage vMotion operations."
This happens regardless even if you set the parameters above - in other words, try as best as possible to avoid putting the snapshot files on a datastore away from the parent -flat file disks if all the datastores involved are backing an SDRS cluster...
Troubleshooting http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1031200
Disable selective VSS writers for troubleshooting
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=5962168
Using custom "pre-freeze" and "post-thaw" scripts.
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=1007696
Details VSS troubleshooting. This article also includes the services that need to be running on the GOS., Issues with quiescing.
When performing cloning on vSphere v5.x on a VM with snapshots
This is what's been observed: Base disk + snapshot will be copied over to the destination VM merging the snapshot(s) into a single VMDK at destination.
When you've run out of space on the datastore and snapshots cannot be deleted
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004545
This post details the steps to take with a command line tool provided you already have another datastore with sufficient space or have been able to increase the space on the same datastore that had run out of space.
There is a limit on how many open vmdk files an ESXi host can address depending on the VMFS version.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004424
This article is very interesting technically. Covers all versions of ESXi till date. There are changes to the HEAP size between version updates. Useful. Here's the table of limits reproduced:
I started out looking for supporting articles but ended up going in and out of KBs and losing track of what belongs to what, where belongs to where. Hence this post. It's mostly my notes of what I think will be useful and important while troughing through the maze of KB articles.
Start here (Understanding how Snapshots work on different versions of ESX/ESXi)
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1015180
- Quiesce: If the
flag is 1 or true, and the virtual machine is powered on when the snapshot is taken, VMware Tools is used to quiesce the file system in the virtual machine. Quiescing a file system is a process of bringing the on-disk data of a physical or virtual computer into a state suitable for backups. This process might include such operations as flushing dirty buffers from the operating system's in-memory cache to disk, or other higher-level application-specific tasks.
Note: Quiescing indicates pausing or altering the state of running processes on a computer, particularly those that might modify information stored on disk during a backup, to guarantee a consistent and usable backup. Quiescing is not necessary for memory snapshots; it is used primarily for backups. - If the virtual disk is larger than 2TB in size, the redo log file is of
format.- -sesparse.vmdk .vmsd
The.vmsdfile is a database of the virtual machine's snapshot information and the primary source of information for the snapshot manager. The file contains line entries which define the relationships between snapshots as well as the child disks for each snapshot.TheSnapshot .vmsn .vmsnfile includes the current configuration and optionally the active state of the virtual machine.- The above files will be placed in the working directory by default in ESX/ESX 3.x and 4.x.
- In ESXi 5.x and later snapshots descriptor and delta VMDK files will be stored in the same location as the virtual disks (which can be in a different directory to the working directory).
- When removing a snapshot, the snapshot entity in the snapshot manager is removed before the changes are made to the child disks. The snapshot manager does not contain any snapshot entries while the virtual machine continues to run from the child disk.
- During a snapshot removal, if the child disks are large in size, the operation may take a long time. This can result in a timeout error message from either VirtualCenter or the VMware Infrastructure Client.
The child disk
The child disk, which is created with a snapshot, is a sparse disk. Sparse disks employ the copy-on-write (COW) mechanism, in which the virtual disk contains no data in places, until copied there by a write. This optimization saves storage space. The grain is the unit of measure in which the sparse disk uses the copy-on-write mechanism. Each grain is a block of sectors containing virtual disk data. The default size is 128 sectors or 64KB
The disk chain
Generally, when you create a snapshot for the first time, the first child disk is created from the parent disk. Successive snapshots generate new child disks from the last child disk on the chain. The relationship can change if you have multiple branches in the snapshot chain.
This diagram is an example of a snapshot chain. Each square represents a block of data or a grain as described above:

- Reverting virtual machines to a snapshot causes all settings configured in the guest operating system since that snapshot to be reverted. The configuration which is reverted includes, but is not limited to, previous IP addresses, DNS names, UUIDs, guest OS patch versions, etc.
http://blogs.vmware.com/vsphere/2011/09/storage-vmotion-storage-drs-virtual-machine-snapshots.html
"It should also be noted that if you do a Storage vMotion of a VM with snapshots and the VM has the workingDir parameter set, theworkingDir setting will be removed from the .vmx & the .vmsn snapshot data file will be moved to the home folder of the VM on the destination datastore. You do get a warning in the migration wizard about this"
"Therefore, if you use the snapshot.redoNotWithParent = "TRUE" parameter, you should refrain from doing Storage vMotion operations."
This happens regardless even if you set the parameters above - in other words, try as best as possible to avoid putting the snapshot files on a datastore away from the parent -flat file disks if all the datastores involved are backing an SDRS cluster...
Troubleshooting http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1031200
Disable selective VSS writers for troubleshooting
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=5962168
Using custom "pre-freeze" and "post-thaw" scripts.
Covers SYNC and LGTO_SYNC drivers, not VSS.
This article details why the VM may become unresponsive and seem "hung" during a snapshot process.http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=1007696
Details VSS troubleshooting. This article also includes the services that need to be running on the GOS., Issues with quiescing.
When performing cloning on vSphere v5.x on a VM with snapshots
This is what's been observed: Base disk + snapshot will be copied over to the destination VM merging the snapshot(s) into a single VMDK at destination.
When you've run out of space on the datastore and snapshots cannot be deleted
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004545
This post details the steps to take with a command line tool provided you already have another datastore with sufficient space or have been able to increase the space on the same datastore that had run out of space.
There is a limit on how many open vmdk files an ESXi host can address depending on the VMFS version.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004424
This article is very interesting technically. Covers all versions of ESXi till date. There are changes to the HEAP size between version updates. Useful. Here's the table of limits reproduced:
| Version/build | Default heap amount | Default allowed open VMDK storage per host | Minimum heap amount | Maximum heap amount | Maximum heap value | Maximum open VMDK storage per host |
| ESXi/ESX 3.5/4.0 | 16 MB | 4 TB | N/A | N/A | N/A | N/A |
| ESXi/ESX 4.1 | 80 MB | 8 TB | N/A | 128 MB | 128 | 32 TB |
| ESXi 5.0 Update 2 (914586) and earlier | 80 MB | 8 TB | N/A | 256 MB | 255 | 25 TB |
| ESXi 5.0 Patch 5 (1024429) and later | 256 MB | 60 TB | 256 MB | 640 MB | 255 | 60 TB |
| ESXi 5.1 Patch 1 (914609) and earlier | 80 MB | 8 TB | N/A | 256 MB | 255 | 25 TB |
| ESXi 5.1 Update 1 (1065491) and later | 256 MB | 60 TB | 256 MB | 640 MB | 255 | 60 TB |
Disks (VMDK) larger than 2TB (for ESXi 5.5 with VMFS5 only. If using NFS, backend must be on file system that has large file support like EXT4. Extending disks beyond 2TB also requires the use of the Web Client or vCLI)
http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=2058287
Changes in virtual machine snapshots for VMDKs larger than 2 TB:
- Snapshots taken on VMDKs larger than 2 TB are now in Space Efficient Virtual Disk (SESPARSE) format. No user interaction is required. The redo logs will be automatically created as SESPARSE instead of VMFSSPARSE (delta) when the base flat VMDK is larger than 2 TB.
- Extending a base flat disk on VMFSSPARSE or SESPARSE is not supported.
- The VMFSSPARSE format does not have the ability to support 2 TB or more.
- VMFSSPARSE and SESPARSE formats cannot co-exist in the same VMDK. In a virtual machine, both types of snapshot can co-exist, but not in the same disk chain. For example, when a snapshot is taken for a virtual machine with two virtual disks attached, one smaller than 2 TB and one larger than 2 TB, the smaller disk snapshot will be VMFSSPARSE the larger disk snapshot will be SESPARSE.
- Linked clones will be SESPARSE if the parent disk is larger than 2 TB.
What else can cause snapshots consolidation to fail?
Main reference article in spanish:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2046576
1. Locks (files are locked)
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=10051
2. Temporary loss of communication between vCenter and ESXi hosts during confirmation - this does not mean that the ESXi hosts are shown to be disconnected from vCenter. To "restore" connectivity restart management agents from the host. (My note from field experience - there is a chance that during the restart of the management agents, your host may really get disconnected from vCenter AND if your cluster is EVC enabled, you will have to shutdown all the running VMs on that host in order for that host to rejoin the EVC cluster - so beware!)
3. A snapshot configuration file with extension .vmsd in the VM home directory may interfere. Rename, move or delete that file.
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1003490
Main reference article in spanish:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2046576
1. Locks (files are locked)
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=10051
2. Temporary loss of communication between vCenter and ESXi hosts during confirmation - this does not mean that the ESXi hosts are shown to be disconnected from vCenter. To "restore" connectivity restart management agents from the host. (My note from field experience - there is a chance that during the restart of the management agents, your host may really get disconnected from vCenter AND if your cluster is EVC enabled, you will have to shutdown all the running VMs on that host in order for that host to rejoin the EVC cluster - so beware!)
3. A snapshot configuration file with extension .vmsd in the VM home directory may interfere. Rename, move or delete that file.
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1003490
Friday, June 20, 2014
Things to look out for when using VMware PVSCSI
Well, since VMXNET3 is optimum, why not PVSCSI?
Rolling out to a production environment we have to make sure we know the possible caveats and limitations so that the stakeholders can be informed and operations have the correct information for deployments.
Following is a summary of things to look out for based on URL here:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1010398
Rolling out to a production environment we have to make sure we know the possible caveats and limitations so that the stakeholders can be informed and operations have the correct information for deployments.
Following is a summary of things to look out for based on URL here:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1010398
- The VMware PVSCSI adapter driver is also compatible with the Windows Storport storage driver
- PVSCSI adapters are not suited for DAS environments.
- Cannot be used as a boot disk for Red Hat Enterprise Linux (RHEL) 5 (32 and 64 bit) and all update releases
- Hot-adding a PVSCSI adapter is only supported for those versions that support booting from a PVSCSI adapter.
- Hot add or hot remove requires a bus rescan from within the guest.
- Disks with snapshots might not experience performance gains when used on Paravirtual SCSI adapters if memory on the ESX host is over committed.
- Do not use PVSCSI on a virtual machine running Windows with spanned volumes. Data may become inaccessible to the guest operating system.
- If you upgrade from RHEL 5 to an unsupported kernel, you might not be able to access data on the virtual machine's PVSCSI disks. You can run vmware-config-tools.pl with the kernel-version parameter to regain access.
- If a virtual machine uses PVSCSI, it cannot be part of a Microsoft Cluster Server (MSCS) cluster.
I remember seeing somewhere some other considerations for View deployments and will update this post once there is more information.
Have a great day ahead!
Wednesday, April 30, 2014
A timeout (30000 milliseconds) was reached while waiting for a transaction response from the (name-of-service) service (WIP)
Post is purely to reference bookmarks during troubleshooting (Work-In-Progress)
General consensus so far looks like it's related to some third party application issues.
http://www.eversity.nl/blog/2012/08/a-timeout-30000-milliseconds-was-reached-while-waiting-for-a-transaction-response-from-the-name-of-service-service/
http://social.technet.microsoft.com/Forums/windowsserver/en-US/77a521a1-e3d5-4ab2-9c0f-be4a5498ce1c/windows-server-2008-sp2-stops-responding-as-multiple-services-timeout?forum=winserverTS
This thread has a bit more variations to the issue:
http://social.technet.microsoft.com/Forums/en-US/2c4b8121-da1c-4c11-b11d-2dff099ba245/windows-server-2008-r2-sp1-rds-hang-and-stop-responding-new-rdp-session-already-connected-session?forum=winserverTS
Official articles on how to change timeout. May not solve the root cause.
http://support.microsoft.com/kb/922918 (EventID: 7011)
http://social.technet.microsoft.com/wiki/contents/articles/1458.event-id-7011-basic-service-operations.aspx
Other (may be related)
http://technet.microsoft.com/en-us/library/cc756342%28v=ws.10%29.aspx (EventID: 7009)
Affecting VMtools:
http://ambitech.blogspot.sg/2013/01/esxi-5x-error-messages-in-windows-vm.html
Based on article comments, recommendation of not "updating OS patches + VMtools installation together" is not conclusive. (as in my environment, we patch first, then update tools)
Normal client OS with SSD:
http://www.bradymoritz.com/a-timeout-was-reached-30000-milliseconds-while-waiting-for-the
Seem to point to NOT disk issues. Hmmm...
General consensus so far looks like it's related to some third party application issues.
In my environment, eventlogs reported multiple user registry leaks.
My guess it has to do with the server being under load or some hardware (possibly disk?) related issues combined with the software combination and communications between tiers.
http://www.eversity.nl/blog/2012/08/a-timeout-30000-milliseconds-was-reached-while-waiting-for-a-transaction-response-from-the-name-of-service-service/
http://social.technet.microsoft.com/Forums/windowsserver/en-US/77a521a1-e3d5-4ab2-9c0f-be4a5498ce1c/windows-server-2008-sp2-stops-responding-as-multiple-services-timeout?forum=winserverTS
This thread has a bit more variations to the issue:
http://social.technet.microsoft.com/Forums/en-US/2c4b8121-da1c-4c11-b11d-2dff099ba245/windows-server-2008-r2-sp1-rds-hang-and-stop-responding-new-rdp-session-already-connected-session?forum=winserverTS
Official articles on how to change timeout. May not solve the root cause.
http://support.microsoft.com/kb/922918 (EventID: 7011)
http://social.technet.microsoft.com/wiki/contents/articles/1458.event-id-7011-basic-service-operations.aspx
Other (may be related)
http://technet.microsoft.com/en-us/library/cc756342%28v=ws.10%29.aspx (EventID: 7009)
Affecting VMtools:
http://ambitech.blogspot.sg/2013/01/esxi-5x-error-messages-in-windows-vm.html
Based on article comments, recommendation of not "updating OS patches + VMtools installation together" is not conclusive. (as in my environment, we patch first, then update tools)
Normal client OS with SSD:
http://www.bradymoritz.com/a-timeout-was-reached-30000-milliseconds-while-waiting-for-the
Seem to point to NOT disk issues. Hmmm...
Monday, April 28, 2014
How-To fix RDP connection issue with error "The Local Security Authority cannot be contacted"
Can be caused by:
- User must change password on next logon and RDC is set to use only Network Level Authentication. Affects "workgroup" computers or computers on another domain (compared to the one you're logging in from).
- Missing language pack
References:
On how to disable NLA (assuming you can get access to your remote server using the suggested methods:
Tuesday, April 22, 2014
Heartbleed remediation for vCenter (build 1750787), ESXi (build 1746018), Web Client Integration plug-in (build 1750778), vSphere C# client (build 1746248)
Glad to report the vCenter update went without a hitch on my home lab. As aways YMMV.
![]() |
Updating to vCenter 5.5.0u1a - install in sequence following custom install. No reboot required. All other components remain the same as 5.5.0u1
|
![]() |
Versions of updated 5.5.0u1a vCenter SSO, Inventory Service, Web Client and vCenter Server.
|
![]() |
| VMware Update Manager will be restarted during installation. |
![]() |
| Web Client Integration Plugin will still have the same name as 5.5.0u1 but the build/version has been updated |
![]() | |
| vSphere Client updated to build 1746248. Not sure if it's only my home NAS that's slow but it looked like before updating, the stats and info page for ESXi hosts would not display properly. |
![]() |
| vSphere Client not displaying ESXi stats properly (before updating; could also be caused by my storage backend) |
Thursday, April 17, 2014
How to change Office 2013 keys
For 32 bit Windows:
cscript "C:\Program Files\Microsoft Office\Office15\OSPP.VBS" /inpkey:yourkeygoeshere
For 64 bit Windows (assuming you are using 32 bit Office):
cscript "C:\Program Files (x86)\Microsoft Office\Office15\OSPP.VBS" /inpkey:yourkeygoeshere
Wednesday, April 2, 2014
Gather information on a domain user (including last logon time, password status, NTFS group membership) without having to use ADUC
From command prompt type:
net user /do logonname
output will be similar to:
C:\Users\username>net user /do usernameexample
The request will be processed at a domain controller for domain thdm.local
User name usernameexample
Full Name FirstnameLastname
Comment
User's comment
Country code 000 (System Default)
Account active Yes
Account expires Never
Password last set 1/1/2014 01:26:20 AM
Password expires 2/1/2014 01:26:20 AM
Password changeable 2/2/2014 01:26:20 AM
Password required Yes
User may change password Yes
Workstations allowed All
Logon script logon.cmd
User profile
Home directory
Last logon 2/4/2014 7:51:17 AM
Logon hours allowed All
Local Group Memberships
Global Group memberships *ACCESS-EVERYTHING
The command completed successfully.
net user /do logonname
output will be similar to:
C:\Users\username>net user /do usernameexample
The request will be processed at a domain controller for domain thdm.local
User name usernameexample
Full Name FirstnameLastname
Comment
User's comment
Country code 000 (System Default)
Account active Yes
Account expires Never
Password last set 1/1/2014 01:26:20 AM
Password expires 2/1/2014 01:26:20 AM
Password changeable 2/2/2014 01:26:20 AM
Password required Yes
User may change password Yes
Workstations allowed All
Logon script logon.cmd
User profile
Home directory
Last logon 2/4/2014 7:51:17 AM
Logon hours allowed All
Local Group Memberships
Global Group memberships *ACCESS-EVERYTHING
The command completed successfully.
Monday, February 17, 2014
Can I perform a P2V conversion on an Active Directory domain controller? (Note!! Use at your own risk!)
Updated 2014-Apr:
Summary; you can do it. Just make sure all the FSMO roles are on the DC that is being P2Ved. Also Microsoft test-case is based on only ONE DC. The ramifications of performing this action on a mult-DC environment is not clear.
In essence, this P2V test case is based on SCVMM and not VMware Converter. There are multiple steps involved. SCVMM will use VSS to take a snapshot of the current state of the AD and simultaneously create a VM (on MS platform) and start cloning.
VMware Converter process:
From the horses' mouth, this is how it coordinates with the ESXi layer, the source VM and the destination target VM.
Original post 17 Feb 14
NOTE - Use these only at your OWN RISK. I cannot be held responsible for any issues that may arise through applying any of the following. It is generally a well known "no-no" to P2V and V2V a DC that is pre-2012.
Summary; you can do it. Just make sure all the FSMO roles are on the DC that is being P2Ved. Also Microsoft test-case is based on only ONE DC. The ramifications of performing this action on a mult-DC environment is not clear.
In essence, this P2V test case is based on SCVMM and not VMware Converter. There are multiple steps involved. SCVMM will use VSS to take a snapshot of the current state of the AD and simultaneously create a VM (on MS platform) and start cloning.
VMware Converter process:
From the horses' mouth, this is how it coordinates with the ESXi layer, the source VM and the destination target VM.
1. Authenticate the Source Machine. (I take this as logging on to the source machine)
2. Get the Source VM information.
3. Install the Agent on the Source Computer.
4. Create a new Destination VM.
5. Call the VSS program to Clone or Snapshot the guest
machine internally.
6. Copy the cloned info to the destination machine.
7. Uninstall the agent from the Source Machine.
"We do not invoke any other thing which will cause the
Source Machine to hamper."
Original post 17 Feb 14
NOTE - Use these only at your OWN RISK. I cannot be held responsible for any issues that may arise through applying any of the following. It is generally a well known "no-no" to P2V and V2V a DC that is pre-2012.
(From Microsoft Support - Advisory only - Further details, if any, will be updated as more information becomes available)
Can I perform a P2V conversion on an Active Directory
domain controller?
Yes. You can perform an offline P2V conversion on a
domain controller. Performing the conversion offline helps avoid potential
Active Directory USN rollback issues during the process.
Recommendations:
Offline P2V:
The impact to the original is when you perform P2V, the
source DC will restart into the Windows Preinstallation Environment. It is the
recommended solution if you need to P2V multiple domain controllers.
Online P2V:
SCVMM Online P2V will not impact original Physical
environment, which has been double confirmed with System Center team. But it will cause USN rollback problem for
the virtual environment if you P2V multiple domain controllers. However, if you
only P2V one DC with FSMO roles, it will not cause any problem.
If you P2V only one DC with FSMO role using Online P2V.
Please perform the following steps on the converted DC in virtual machine:
1. Clean up
metadata for DCs no longer exist
Clean up server metadata
2. Please
disable initial synchronization when you start the virtual machine for the
first time:
How to disable initial synchronization
On the PDC, go to the following registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Parameters
Add the following Value:
Value name: Repl
Perform Initial Synchronizations Value type:
REG_DWORD Value data: 0
=============================
Thursday, February 13, 2014
Status check of AD RID pool with email (Powershell)
Import-Module activedirectory
$RIDinfo=dcdiag /test:ridmanager /v | find "Available RID"
send-mailmessage -to demo@somewhere.com -from someone@somewhere.com -subject $RIDinfo -smtpserver 10.10.10.10
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