Yellow Bricks

by Duncan Epping

5

Creating an Image Profile without manually downloading a bundle! (stateless ESXi)

· ·

Just like the past couple of days I’ve been playing around with stateless ESXi. I’ve downloaded multiple ESXi bundles / depots and remembered that there was an easier way of creating an Image Profile.  The image profiles are also available as part of an online depot at vmware.com. So I figured I would start using that one instead of downloading the bundle manually every single time. It is fairly simple to add the online source as a depot:

Add-EsxSoftwareDepot -DepotUrl https://hostupdate.vmware.com/software/VUM/PRODUCTION/main/vmw-depot-index.xml

If you would do a “Get-EsxImageProfile” next you would see all image profiles (see screenshot below) which are part of the depot.

Now you could even compare the two image profiles which would tell you if the image profiles are equal and which VIB has changed. In this case it is one of the primary VIBs “esx-base”:

Compare-EsxImageProfile ESXi-5.0.0-469512-no-tools ESXi-5.0.0-20110904001-notools

Equal               : False
PackagesEqual       : False
RefAcceptanceLevel  : PartnerSupported
CompAcceptanceLevel : PartnerSupported
OnlyInRef           : {}
OnlyInComp          : {}
UpgradeFromRef      : {VMware_bootbank_esx-base_5.0.0-0.3.474610}
DowngradeFromRef    : {}

If you figure by now that all this PowerCLI stuff is not your cup of tea I would like to suggest to check out Alan Renouf’s brand new PowerPack. Alan has GUI’fied the most common tasks which will enable you to click and point instead.

Want to win a free vSphere 5.0 Clustering Tech Deepdive book?

· ·

Want to win a free vSphere 5.0 Clustering Tech Deepdive book? Check out Frank’s article today…

If you follow me on twitter you might have seen my tweets I’m in Copenhagen for the last two weeks. Many followers asked me what I was doing there and were speculating it had something to do with VMworld. Even when replying I was visiting a customer, most dismissed these answers. Unfortunately yesterday Rasmus Jensen (@rasmusjensenvp) spotted me and I’m guessing the secret is out. So I might as well come clean. Yes I’m camping outside the Bella Center.

Patching your Image Profile (stateless ESXi)

· ·

The first patch for ESXi has been released so I figured this was a great time to create and article around how to patch your Image Profile with a new update. The process is fairly straight forward as in this case you will need to create a new image-profile (described here) and link it to a new rule (New-DeployRule and make that rule active (Add-DeployRule). That is what I like about Stateless. You can just prepare a new Image Profile, create a new rule and you are good to go. A reboot of your ESXi host will load up the latest Image Profile. I did this within a couple of minutes and I’m now running build 474610 of ESXi.

While I was playing around I decided to do things in an incorrect order to see if I could break it, and of course I did manage to break it… I managed to fix all of it though. The first thing I did was testing the rule set and repairing it as documented below.

Now if you run into any issues you can repair the ruleset by using the following command:

Get-VMHost <esxi host> | Test-DeployRuleSetCompliance | Repair-DeployRuleSetCompliance

Now if your host boots and mentions that there’s no rule associated you might want to try the following:

Get-DeployRule

If your newly created rule is returned you will want to make sure it is active:

Get-DeployRuleSet

If there’s nothing listed it means no rules are currently active (active ruleset is what the documentation will refer to). You you can set the rule as active as follows:

Set-DeployRuleSet -DeployRule <name of rule>

Everyone who is considering using Auto-Deploy I would most definitely recommend to explore these commands and to try to break things and fix it. Document your steps along the way, I am certain it will be valuable at some point!

Stripping your Stateless image

· ·

I was just playing around with Stateless again, aka auto-deploy, and I was wondering how far I could strip the image down to the bare minimum and what the difference would be. I loaded the standard software depot and cloned an existing image profile to a new image profile, for more details on how to do this check the post I published a couple of days ago. I figured I would export this newly create image profiles first so I could see the size of the bundle when exported. I cloned and exported the “ESXi-5.0.0-469512-no-tools” image profile and checked the details:

ESXiStateless.zip 137,869 KB

Now the first thing to do was figuring out which VIBs were part of this image profile, you can do this fairly simple by using the command below. Note that I exported the results to a CSV file just to make it easier if I would need to add VIBs later:

Get-EsxImageProfile <image profile name>  | Select-Object -ExpandProperty VibList | Select name | export-csv c:\tmp\VIBs.csv

Now this returns the full list of all the VIBs in a CSV file with just the names of the VIBs. There are 2 core VIBs (esx-base and esx-tboot) which are required for booting. I also kept the e1000 VIB as I knew I needed it. The e1000 VIB requires the “misc-drivers” VIB so I was left with 4 VIBs:

esx-base
esx-tboot
e1000
misc-drivers

Stripping the rest of the VIBs is fairly simple. Note that you will need to replace <image profile name> with the actual name of your image profile and <package name> with the name of the package you would like to remove:

Remove-EsxSoftwarePackage -ImageProfile <image profile name> -SoftwarePackage <package name>

So I stripped it completely and exported the image profile again and this was the result:

Thinner.zip 131,457 KB

Note that you can actually check which VIBs are part of your image profile, which is what I used to validate I removed all unnecesarry VIBs:

Get-esximageprofile <image profile name> | Select-Object -ExpandProperty VibList

That is a whopping 6MB shaved off! (By the way this is without the HA-Agent. The size of the completely stripped image profile with the HA agent is 143,679KB) Was it a useful exercise? Yes it was as it helped me understanding the process a lot better… Is it useful to strip all the drivers from your image profile? No it is not, you will only save 6MB which is close to nothing compared to the overall size of 131 MB. I did manage to boot the image correctly, but once again there’s really no point from a memory perspective to go through this exercise.

The thing that does make a huge difference is using the no-tools image profile, but there is a serious implication. When you do not include VMware Tools you will need to have a different mechanism for distributing VMware Tools which will probably complicate things from an operational perspective. I guess you will need to decide if the reduction in MBs is worth the effort and is worth the risk of having a “1 of a kind” environment. I know I will keep it vanilla from now on,

 

Does SRM support Storage DRS? No it does not!

· ·

During VMworld I received multiple questions around support for vSphere Storage DRS with vSphere Site Recovery Manager (SRM), we even had this question during our session and my answer was “Yes it does”. During some of the other sessions presenters stated that it was unsupported. Scott Lowe also mentions recalling the fact that it was mentioned somewhere down the line to be unsupported. Now although the Resource Management Guide for vSphere 5.0 on page 91 currently says it is supported it is not supported. Yes I know I stated it was supported but unfortunately the document is incorrect and the information provided to me was outdated. Although I verified the facts, I was not informed about this change. Hopefully this will not happen again and my apologies for that.

Now lets give the raw facts first, SRM does not support Storage vMotion and SRM does not support Storage DRS. The reason that SRM does not support Storage vMotion (and subsequently Storage DRS) is because it changes the location of the virtual machine without SRM being aware of it. After the location of the virtual machine has changed the VM that was originally protected by SRM will not be protected anymore which can have an impact on your RTO. These are the raw facts. I have requested the SRM team to document this in a KB to make sure everyone understands the reason and the impact.

The question of course is… will it work? My colleague Cormac has tested it and you can read his observations here.

This statement is documented in the SRM releasenotes: http://www.vmware.com/support/srm/srm_releasenotes_5_0_0.html

Interoperability with Storage vMotion and Storage DRS:
Due to some specific and limited cases where recoverability can be compromised during storage movement, Site Recovery Manager 5.0 is not supported for use with Storage vMotion (SVmotion) and is not supported for use with the Storage Distributed Resource Scheduler (SDRS) including the use of datastore clusters.

** update: I followed the documentation which apparently was incorrect. Documentation bug has been filed, should be update in the near future. **
** update: Link to SRM releasenotes with statement added. **