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  • 1.  DRS power-on algorithm?

    Posted Sep 09, 2007 06:42 PM

    So, I'm in the last couple of weeks of migrating my last farm to VI3 from ESX 2.5.x...

    I migrated about 30 more VMs this weekend to a cluster of 9 existing host servers. I have DRS set for it to decide the best place to power on VMs...

    As I powered on the VMs (this was over an entire day of migrating), I noticed that DRS kept chosing one of my host servers a lot more than the other host servers...

    When the migration was done, I noticed that one host server showing yellow in Virtual Center... I went and looked at all the hosts...

    Host 1 - 15 VMs

    Host 2 - 15 VMs

    Host 3 - 20 VMs

    Host 4 - 21 VMs

    Host 5 - 16 VMs

    Host 6 - 18 VMs

    Host 7 - 15 VMs

    Host 8 - 29 VMs[/b]

    Host 9 - 14 VMs

    Hosts 1-7,9 all had %CPU in the 26%-44% range, Host 8 was at 64%

    Hosts 1-7,9 all had %memory in the 48%-72% range, Host 8 was at 82%

    So why did DRS continue to power on VMs on Host 8 instead of using the other host servers?

    I manually migrated some VMs off of Host 8 to distribute the load better... but I wish I knew how this worked and why it distrubuted the load that way.



  • 2.  RE: DRS power-on algorithm?

    Posted Sep 09, 2007 06:46 PM

    Do you have any DRS rules set?



  • 3.  RE: DRS power-on algorithm?

    Posted Sep 09, 2007 09:04 PM

    Yeah, I have a bunch of rules for the VMs that were already on those host servers... but nothing that should have applied to the 30 VMs I migrated over this weekend.



  • 4.  RE: DRS power-on algorithm?

    Posted Sep 09, 2007 09:07 PM

    Do any of these rules contain more than two VMs (there's a bug with those rules)?

    Try removing the rules or change them to only reference two VMs - this should start the automatical migration of VMs to other hosts.



  • 5.  RE: DRS power-on algorithm?

    Posted Sep 09, 2007 09:45 PM

    I knew about the bug with trying to keep [b]separate[/b][/i] more than 2 VMs at a time... so I got rid of all those rules a while back...

    I do still have rules that keep [b]together[/b][/i] more than 2 VMs though. They actually seem to be working... Is there a bug with those too?



  • 6.  RE: DRS power-on algorithm?

    Posted Sep 09, 2007 09:58 PM

    I'm not sure if this bug affects rules that keep VMs together, but... I personally (just to be safe :smileywink:) only use rules (regardless of the rule type) containing two VMs.