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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hello,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We have a OpenStack setup with a large number of compute nodes spread in different subnets which are represented as different physnet’s in OpenStack.<o:p></o:p></p><p class=MsoNormal>When we start an instance we see that the scheduler choose a compute node and tries to spawn the instance, then it sees its not in the right physnet and choose a different compute node.<o:p></o:p></p><p class=MsoNormal>In our case this takes around 4 – 10 attempts. All this attempts counts for the “scheduler_max_attempts” which default value is 3. We increase this value to prevent errors, but it’s still very inefficient especially in a large environment.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there a way that the scheduler knows the physnet/subnet position of the compute nodes before the instance tries to spawn?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in advance!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Greetings <o:p></o:p></p><p class=MsoNormal>Chris<o:p></o:p></p></div></body></html>