Yellow Bricks

by Duncan Epping

Archives for 2009

11 December 2009 – Dutch VMUG

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It is time to take out your agenda open it on December the 11th 2009 and write down “Dutch VMUG”. It’s the fifth edition of this annual event and of course our fearless VMUG leader Viktor expects to set a new attendee record. Just for the record the last edition had little over 500 attendees, yes it has become a mini VMworld. I wouldn’t be surprised if they would hit 600-700 this time.

I can recommend every single reader from the Benelux, and outside, to attend this awesome event. It will have a mix of overview sessions and technical deepdives. Vendors(EMC, VMware, Veeam, Vizioncore) will mostlikely be presenting but also expect presentations from VMUG members and experts like Eric Sloof, Bouke Groenescheij and Gabrie van Zanten. The agenda will be announced within a couple of weeks and registration will also be opened soon.

There’s more info to be found here.

Oracle feels that not many people want to run their apps in a virtual environment!

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I just noticed the following article by “Oracle Storage Guy“:

Re: Need a favor – Oracle

You are not going to believe this.  Some VMware folks met with Charles Phillips, the president or CEO of Oracle and he said no customers had ever mentioned to him that they wanted Oracle to support their products on VMware.  Or modify the licensing scheme.  He offered if anyone knew of customers who did want better or more support for Oracle on VMware, or virtualization friendly licensing, to email him directly.  His email is Charles.phillips@oracle.com and he really needs to hear that customers run Oracle on VMware, and better support / licensing would be nice!

Apparently VMware provided Oracle a list of customers that wanted Oracle to support their Apps / Databases on VMware and even better change the licensing scheme to one that actually makes sense in 2009. Of course Charles Philips, Oracles President, responded that he never heard about this before. Charles apparently said that anyone who is looking for Oracle’s support or a licensing scheme based on vCPUs should drop him an email. Oracle customers can contact Charles.

Thanks Charles for taking this serious.

Long Distance VMotion

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As you might have noticed last week I’m still digesting all the info from VMworld. One of the coolest new supported technologies is Long Distance VMotion. A couple of people already wrote a whole article on this session so I will not be doing this. (Chad Sakac, Joep Piscaer) However I do want to stress some of the best practices / requirement to make this work.

Requirements:

  • An IP network with a minimum bandwidth of 622 Mbps is required.
  • The maximum latency between the two VMware vSphere servers cannot exceed 5 milliseconds (ms).
  • The source and destination VMware ESX servers must have a private VMware VMotion network on the same IP subnet and broadcast domain.
  • The IP subnet on which the virtual machine resides must be accessible from both the source and destination VMware ESX servers. This requirement is very important because a virtual machine retains its IP address when it moves to the destination VMware ESX server to help ensure that its communication with the outside world (for example, with TCP clients) continues smoothly after the move.
  • The data storage location including the boot device used by the virtual machine must be active and accessible by both the source and destination VMware ESX servers at all times.
  • Access from VMware vCenter, the VMware Virtual Infrastructure (VI) management GUI, to both the VMware ESX servers must be available to accomplish the migration.

Best practices:

  • Create HA/DRS Clusters on a per site basis. (Make sure I/O stays local!)
  • A single vDS (like the Cisco Nexus 1000v) across clusters and sites.
  • Network routing and policies need to be synchronized or adjusted accordingly.

Most of these are listed in this excellent whitepaper from VMware, Cisco and EMC by the way.

Combining this current available technology with what Banjot discussed during his VMworld session regarding HA futures I think the possibilities are endless. One of the most obvious ones is of course Stretched HA Clusters. When adding VMotion into the mix a stretched HA/DRS Cluster would be a possibility. This would require other thresholds of course but how cool would it be if DRS would re-balance your clusters based on specific pre-determined and configurable thresholds?!

Stretched HA/DRS Clusters would however mean that the cluster needs to be carved into sub-clusters to make sure I/O stays local. You don’t want to run your VMs on site A while their VMDKs are stored on site B. This of course depends on the array technology being used. (Active / Active, as in one virtual array would solve this.) During Banjot session it was described as “tagged” hosts in a cross site Cluster and during the Long Distance VMotion session it’s described as “DRS being aware of WAN link and sidedness”. I would rather use the term “sub-cluster” or “host-group”. Although this all seems to be still far away it seems to be much closer than we expect. Long Distance VMotion is supported today. Sub-clusters aren’t available yet but knowing VMware, and looking at the competition,  they will go full steam ahead.

Referrers top 10

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I was just looking at my blog statistics; one of the most interesting part is referrer section. Referrers give you a good idea of where your visitors are coming from which can be used to write specific content. I removed Google.com from the top-10 by the way. On average I have little over 4000 unique visits on a working day, during the weekend most of you seem to spending time with your kids/wife/friends as I only hit 1300 on average. But who cares anyway, this post is about the top 10 referrers:

  1. vsphere-land.com
  2. vmware.com/vmtn/planet/v12n
  3. vmetc.com
  4. simonlong.co.uk
  5. vmwaretips.com
  6. blog.fosketts.net
  7. communities.vmware.com
  8. blogs.netapp.com
  9. boche.net/blog
  10. blog.scottlowe.org

I’m a bit surprised to see Simon Long so high up this list but I guess his VCP4 vSphere Study Notes post has been really popular as this is the specific article that drives most of the traffic from his site to mine. I guess the rest of the list makes sense looking at the popularity of the blogs.

Thanks everyone for referring to my blog and a special thanks to Eric Siebert as he alone is responsible for the same amount of traffic as numbers 2 to 10 combined!

HA: Did you know?

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Did you know that…

  • the best practice to increase the isolation response time(das.failuredetectiontime) from 15000 to 60000 for an Active/Standby situation for your service console has been deprecated as of vSphere.
    (In other words for active/standby leave it set to the default 15000 for vSphere)
  • the limit of 100 VMs per host is actually “100 powered on and HA enabled VMs”. Of course this also goes for the 40 VM limit  for clusters with more than 8 hosts.
  • the limit of 100VMs per host in an HA cluster less than 9 hosts is a soft limit.
  • das.isolationaddress[0-9] is one of the most underrated advanced settings.
    It should be used as an additional safety net to rule out false positives.

Just four little things most people don’t seem to realize or know…