HA and DRS ............. EVC

• HA and DRS ( Cluster Features )

• HA - High Availability

• It is mainly focus on host failure mechanism .

• HA has back end process like

• Once we enable HA under the cluster , HA will automatically install agent called FDM on all ESXi host

• FDM is installed it will through the election process

• In the election process it will be electing the master and slave based on MOID number and Data store count .

• Once host got failed all VM's will be powered off and FDM agent will take care of migrations , It will power the VM's

• Yes in HA we have down time .

• DRS ( Distributed resource scheduler )

• It will mainly focusing on load management of CPU , memory of VM's

• IF we see any high load on one esxi DRS will auto migrate VM's to the other ESXi hosts to balance the load .

• We don't have any downtime in DRS ( All migrations are live Migrations )

• DRS :

• Fully Automated

• Partially Automated

• Manually Automated

• In our infra we have enabled with fully automated for the smoother DRS migrations

Minimum Requirements for Migration ( HA , DRS , Manual )

1.Same CPU Family 2.Common Storage / Shared Storage 3.VMKernel Adapter on ESXI with VMotion

EVC :::::: EVC Enhanced VMotion Compatibility

EVC can be enabled on the cluster level

Purpose: If my cluster is configured with a different CPU Family ( Version or model ) then enabling EVC will help in migrations .