AZ 104 Compute
Virtual Machines
Each VM has atleast 2 disks OS and Temp
OS disk reg as SATA
Temp disk:
Data disk : to store app data. The size of VM decides how many DD can you attach
Storage options
Premium
managed disks
availability set
vm must be created to be added to AS
to move a vm from AS it must be deleted
vms in AS run across multiple physical severs , storage racks and network switches
each VM in AS is placed in one fault domain and one update domain
update domain : An update domain is a group of nodes that are upgraded together during the process of a service upgrade (or rollout).
fault domain : A fault domain is a group of nodes that represent a physical unit of failure
Availability zone
unique physical location within Azure region
each AZ is made up of one or more DC
theres a minimum of 3 separate zone in each enabled region
Azure services
zonal : zone specific e.g. VM
zone redundant : e.g. Azure storage
VM Scale sets
all vmss are created from the same base OS
vmss support ALB for basic L4 load balancing
vmss support App Gateway to support L7 load balancing
vmss can support upto 1000 standard vms and upto 600 custom vms
autoscaling
VM extensions
When a virtual machine requires software installation or anti-virus protection, or the machine needs to run a script, you can use virtual machine extensions to manage these processes.
Keep in mind that Custom Script Extensions only have 90 minutes to execute
Azure App Service
one or more app can be run on the same app service plan
an app service plan defines 3 settings
region
no of vm instances
vm sizes small, medium and large
scaling
scales memory , cpu and disks
scaling out limit is 30 but can go more with isolated
auto scaling triggers
metric based
time based
deployment slots
are live web apps that have their own host names
only available for std, prm and isolated
advantages
validation before deploy to live
low downtime or zero downtime
restore back to last known good site
Azure containers
container group
A container group is a collection of containers that get scheduled on the same host machine. The containers in a container group share a lifecycle, resources, local network, and storage volumes.
deploy multi container group using ARM or YAML files
Docker
available for both windows and linux and can be hosted in Azure