Azure VM Tiers

Basic tier: Introductory level

Standard tiers:

A-series: Standard level

D-series: Faster processors, high memory-to-core ratio, SSD temp disk

Dv2-series: 35% faster than D series. Same memory/disk

DS-series: Premium storage (SSDs)

G-series: Biggest VM size. Intel Xeon E5 V3 processors

GS-series: Premium storage (SSDs)


Key VM IaaS Questions

  • CPU
  • RAM
  • NIC
  • Temp disk performance
  • Data disk
  • Cache size
  • Max data disk IOPS/bandwidth


  • Fault Domains => single point of failure (e.g. all servers in same rack fail ‘cos power fails). Place resources in separate fault domains
  • Update Domains => software updates (e.g. when server OS is updated then VMs are shifted off and then shifted back)

Azure Availability Sets => fault or update won’t take workload down. So distribute workloads across availability sets. Each workload in its own availability set (e.g. SQL server and web server in same availability set).

Note: VMs in same availability set should be of same sort.


Leave a Reply

Your email address will not be published. Required fields are marked *