VMware

VMware Server / ESX content

On VMware Fusion updating

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I’ve not had a lot of luck in the past with updating my VMware Fusion installs. Since version 5.x and upwards through to 6.x I’ve always had some annoying bugs or issues crop up when updating Fusion on my work machine. Whether these be relating to functionality I am used to changing, or bugs that interfere with my use of the software, there has always been something that goes wrong when I update.

So here is some general advice for when a new update for Fusion appears (this is what I now do before updating to the latest and so-called greatest version!)

  • Wait. Don’t update as soon as the new release is out. I generally wait about a month now. Generally this should be enough time for the Fusion team to correct initial problems with releases and give them time to submit a follow up patch to fix issues.
  • Keep tabs on the VMware communities forums for Fusion – users will often post issues with new releases here – judging on how much activity appears after a new release, you can generally tell whether its been a bad release or not.
  • Read the release notes in detail. Does the new release really give you any benefit? Have they patched vulnerabilities, or just simply added more features? What existing issues have been fixed? Make your decision to update based on the release notes. Sometimes a new release might not add any value for the way you use the product, and may add 10 new features. You can almost be sure that at least one of those new features is bound to introduce some sort of bug. (This is the nature of new features being added to any software in general, not just Fusion!)

 

 

Cloning and running a duplicate vCenter instance on the same network – process and gotchas

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Recently I needed to clone a vSphere environment (vCenter 5.0.0) for testing purposes. This environment needed to be cloned to have an exact replica of the vCenter server and SQL database server for various tests/upgrades to be performed on it. As for ESXi hosts, a few were being split off the original environment and added to the duplicate vSphere environment.   All the Windows configuration and SQL server configuration needed to be retained, so my high-level plan was as follows:

  • Deploy a new Windows domain (it had to be the same domain functional level and the DC needed to run the same OS as the original)
  • Hot cloned the existing production vCenter and SQL servers
  • Split off the few ESXi physical hosts that were going to be added to the newly cloned environment later on (removed from prod clusters)
  • The new machines needed to run on the same VLAN and IP ranges as the originals too, which made things even more complex, so I made sure to keep the vNICs in the SQL and vCenter cloned VMs disconnected, and disconnected on start up too.
  • Re-IP the cloned VMs after powering them up on one of the split off ESXi hosts (logged in to vSphere client using root credentials) I also re-named their host names and removed from the old domain in, rejoining to the new domain at the same time.
  • Created new service accounts on the newly deployed domain, and reconfigured vCenter services to use these on the cloned machines
  • On the vCenter server there were some changes needed in vCenter config files. This post details most of what needed to be changed:
  • The main change for me though, was I couldn’t see (or didn’t know) how an existing vCenter SQL database would re-act when starting the cloned vCenter on the same VLAN and IP range! There was a strong possibility that this cloned instance could start interfering with the production vCenter and performing operations cross environment. Therefore I decided to create a new SQL vCenter DB. I logged into the cloned vCenter and deleted the old SQL System DSN pointing to the production SQL DB, and created a new SQL database on the cloned SQL box. I then created a new DSN pointing to this, and made sure I searched around for all configuration files on the vCenter server that pointed to the old DSN/SQL server. (I recall there being some references in registry and possibly the vpxd.conf file).
  • Re-creating the right SQL database structure was a bit of a task though. I needed to re-create the structure of the DB without doing an install of course, as I was using the cloned SQL and vCenter machines – with an existing installation on. I followed this KB article, but found a couple of errors/typos in the SQL queries: https://pubs.vmware.com/vsphere-50/index.jsp#com.vmware.vsphere.install.doc_50/GUID-F953497E-2170-4168-806F-6FF0EA6497A7.html by looking at the errors returned in SQL Management studio, you can start to determine where any issues come up and fix the typos. Unfortunately I did not document them myself as I sorted through!
  • Once I was finished with the renaming and IP changes for the cloned machines, I re-connected their vNICs to the relevant networks – happy that they were sufficiently changed!
  • My last issue I came to was that the schema I deployed was one version higher than the vCenter Server build version I was using. I found this out by looking at the vpxd.log file when vCenter failed to start up after deploying the new database schema and content. I fixed this by fudging the version in the database – essentially hard coding the version it wanted into the newly created schema – my thought was that the schema wouldn’t have changed anything old, but rather added new features, so it should be OK. I was right – vCenter started up just fine after this, but I wasn’t happy, so I stopped the services again, deleted the DB, and started again, this time using the right scripts (the scripts referenced in the article link above are located on the vSphere vCenter ISO / media). I had used an ISO with a build increment one higher than the vCenter build I was working with on the cloned VC!) So make sure you use the correct media for your vCenter install here. (I had a vCenter 5.0.0 install, but had deployed schema for 5.0.1!)

 

Hopefully that gives some ideas as to the tasks required when attempting to clone / duplicate an existing vCenter installation, whilst keeping

Fix for VM console error – unable to connect to the mks the operation is not allowed in the current state

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Bit of a strange one this – I have not dug deeper to find the root cause, but here is a quick fix for anyone with the issue.

mks-console-error-vm

 

I found we could not open VM console sessions in a vCenter 5.5 environment today. Usually one’s first thought is that it is a DNS or port issue when you see the classic MKS console error in a VM, but in this case I knew that DNS and ports were not an issue, as RDPing direct to the vCenter Server itself, logging in with the C# client and opening VM consoles from there were giving the exact same message. This was the case for the web client as well as the C# client.

The issue was either with the host that VMs were running on, or with the VMs themselves – the simple fix:

vMotion the VM to another host. As soon as this was done, I could open the console session. The underlying issue is still out there, but I have not had the time to dig any deeper to find out the root cause. More discussion and info available from this VMware communities thread: https://communities.vmware.com/thread/450294

Force ESXi trial license to expire ahead of time

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I recently caught a question on Twitter from Steve Jin, asking if anyone knew how to force an ESXi host to expire it’s trial license for testing purposes.

This got me thinking a bit, and I initially thought the obvious solution would be to set the host’s system clock forward by 60 days for example. I quickly remembered though, that ESXi hosts always seem to count time toward their trial license time based on the number of hours they are powered up for. If you power your host down for a month, and power it back up again, you’ll still have the same amount of time left over on your trial license.

So the next thing I thought, was if I were building a product and protecting it with licensing, surely I would try to prevent people from tampering with the license files. So if someone were to tamper with a license, I could immediately deactivate it, or expire it. This is where I got the idea that worked for Steve’s use case – finding the license.cfg file, and entering some invalid data.

The exact solution, as Steve found, was to find the etc/vmware/license.cfg file on your ESXi host, and tamper with <epoc> the entry, causing the license to become invalid. At this point, any remaining trial license time is invalidated and your license enters an expired state.

 

lice-eval-expire-ESXi

Change the string highlighted above to some random entry, save the file, then reboot your host. Once rebooted, your trial period will have expired!

This could be really useful in some circumstances. Perhaps there is no clear documentation on how a host running VMs in your environment would react if a trial license expired, or you wanted to know how your 3rd party backup software would react to unlicensed hosts. Being able to easily test an expired license scenario can be really handy!

Solving VMware Fusion 6 and Windows 7 VM performance issues

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I have been struggling along with various VM performance issues over the last couple of months using VMware Fusion 5.x, as well as the latest 6.0.3. I just didn’t get the time to dedicate to find a fix for the performance degradation I was seeing until just recently.

I have the following specifications on my Macbook Pro Retina which I use for development purposes:

macspec1

I have a Windows 7 Professional VM running in VMware Fusion, with a spec that I had tried all kinds of different configurations on – mainly 2 vCPUs, and 4GB RAM though. This VM is running on the built-in 256GB SSD.

Nothing seemed to fix the performance issues I was seeing, which was that by at least half way though a typical work day of using Visual Studio and a few tabs of Chrome/IE/Firefox, the VM would slow down to an absolute crawl. I knew it was the VM though, as everything in OSX Mavericks, the host OS was perfectly normal. Most of the time just restarting the Windows VM itself would not help though – I would have to reboot the whole macbook.

The other week I decided enough was enough, and spent a bit of time googling and looking around the VMware Communities forums for a fix. Here is the combination of settings that seems to have resolved my issues now.

  • Settled on a VM spec of 3 x vCPUs (helpful for Visual Studio), and 4GB RAM.
  • Disabled app nap for VMware Fusion (Applications -> Right-click, Get Info on VMware Fusion, and tick the box that says “Prevent App Nap”.
  • Added 3 x new entries into my VM’s configuration file (.vmx file). To edit the .vmx file you’ll need to right-click your VM and select “Show Content”. This will allow you to browse the file content of the VM, and you’ll need to locate your VM’s .vmx file. Right-click this file and open it in your text editor of choice. I added the following lines to the bottom of the file:
MemTrimRate = "0"
sched.mem.pshare.enable = "FALSE"
prefvmx.useRecommendedLockedMemSize = "TRUE"

Don’t forget to disable App Nap for Fusion.

prevent-app-nap
Disable app nap for Fusion