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Learning path

Build in Azure resilience

Availability zones, geo-replication, backup and failover, to survive the bad day on Azure.

25 lessons·~341 min total

Lessons in this path

  1. 1
    Site Reliability AZURE

    Configure AKS node pools across availability zones

    One reliability capability: spread every AKS node pool across the availability zones in its region and serve it through a zone-redundant Standard load balancer, so the cluster keeps running when a single datacentre fails instead of going dark with it.

    14 min
  2. 2
    Site Reliability AZURE

    Use deployment slots to de-risk App Service releases

    One capability for every web app you deploy often: stage a release in a warmed-up slot, validate it against production settings, and swap it into production with no cold start and an instant rollback, so a frequent deployment cadence stops meaning frequent downtime.

    14 min
  3. 3
    Site Reliability AZURE

    Add health checks and autoscale to App Service

    Two settings that turn a single-instance App Service into a self-healing one: a health check path so the load balancer reroutes traffic away from unhealthy instances, and an autoscale rule so the plan adds capacity under CPU and memory pressure instead of falling over.

    13 min
  4. 4
    Site Reliability AZURE

    Run App Service with at least two instances

    A production App Service plan running on a single instance is one routine VM move, patch or restart away from a cold-start interruption or an outright outage. Azure Advisor flags it for a reason: two instances is the floor for surviving the loss of one.

    13 min
  5. 5
    Site Reliability AZURE

    Deploy App Service plans as zone-redundant

    One capability across every web app, API and function on the plan: make sure the plan spreads its instances across availability zones, so the loss of a single datacentre does not take the workload offline.

    14 min
  6. 6
    Site Reliability AZURE

    Enable Application Gateway autoscale and health probes

    One capability across capacity and routing: make sure the gateway in front of your application scales with demand, runs more than one instance, and steers traffic away from backends that are failing, so a traffic spike or a single dead node never becomes an outage.

    14 min
  7. 7
    Site Reliability AZURE

    Deploy Application Gateway across availability zones

    One reliability capability: make sure the gateway that fronts your web traffic survives the loss of a single datacentre, so a zone outage degrades into a few seconds of redistribution rather than a full front-door failure.

    13 min
  8. 8
    Site Reliability AZURE

    Turn on Azure Backup for your virtual machines

    One capability for the whole VM estate: make sure every business-critical virtual machine has a scheduled backup landing in a Recovery Services vault, so a deleted disk, a bad deployment or a corrupted boot volume is a restore, not an outage.

    13 min
  9. 9
    Site Reliability AZURE

    Migrate Cosmos DB to continuous backup for point-in-time restore

    One capability across every Cosmos DB API: move accounts off periodic backup onto continuous backup, so a bad write, a dropped container or a botched deployment can be undone to the second by your own team, in minutes, without a support ticket.

    13 min
  10. 10
    Site Reliability AZURE

    Span Cosmos DB across at least two regions

    A single-region Cosmos DB account is one regional outage away from going dark. Adding a second region, and enabling service-managed failover, turns a full outage into a brief, recoverable event, and Azure Advisor flags every production account that is still single-region.

    14 min
  11. 11
    Site Reliability AZURE

    Enable service-managed failover for Cosmos DB

    One capability across every multi-region Cosmos DB account: make sure that when the primary write region goes dark, Azure promotes a secondary region's write region for you, automatically, instead of leaving your application stuck waiting for a human to react.

    13 min
  12. 12
    Site Reliability AZURE

    Turn on zone redundancy for Cosmos DB regions

    A Cosmos DB region without zone redundancy can park all of its replicas in one datacentre, so a single availability-zone outage takes the region offline. Spreading those replicas across zones keeps the account serving reads and writes while one zone is down, and on most accounts it costs nothing extra.

    14 min
  13. 13
    Site Reliability AZURE

    Give Front Door multiple origins for failover

    One reliability capability: make sure every Azure Front Door origin group has more than one origin, so that when a single backend goes down, traffic shifts to a healthy one instead of the whole site going dark.

    13 min
  14. 14
    Site Reliability AZURE

    Configure load balancer health probes and backend redundancy

    Two settings decide whether an Azure Load Balancer keeps serving when a backend instance dies: a health probe that detects the failure and stops sending traffic to it, and a backend pool with more than one instance so there is somewhere healthy left to send it.

    14 min
  15. 15
    Site Reliability AZURE

    Deploy load balancers with zone-redundant front-ends

    One capability across every Standard Load Balancer in the estate: make sure the front-end that receives and distributes traffic survives the loss of a single availability zone, so a zone fault degrades the service instead of taking it down.

    14 min
  16. 16
    Site Reliability AZURE

    Choose zone-redundant storage for managed disks

    One capability across your VM estate: make sure the disks behind the workloads you cannot afford to lose are replicated across three availability zones, so a single zone going dark does not take the application with it.

    14 min
  17. 17
    Site Reliability AZURE

    Set up disaster recovery with Azure Site Recovery

    One capability for business continuity: replicate your business-critical VMs to a second region, keep the copy continuously up to date, and rehearse the failover regularly so that an outage in one region does not become an outage for your customers.

    14 min
  18. 18
    Site Reliability AZURE

    Tune Azure SQL backup retention and long-term retention

    One capability that decides how far back you can recover an Azure SQL database: set the point-in-time restore window, keep backups geo-redundant so a regional outage cannot take your recovery with it, and add long-term retention where compliance or recoverability needs years, not days.

    14 min
  19. 19
    Site Reliability AZURE

    Protect Azure SQL with auto-failover groups

    One reliability capability for Azure SQL Database and Managed Instance: keep a geo-replicated secondary in a second region behind read-write and read-only listener endpoints, so a regional outage becomes a short failover instead of a day of downtime.

    14 min
  20. 20
    Site Reliability AZURE

    Make Azure SQL databases zone-redundant

    One reliability capability across every provisioned database and elastic pool: make sure the data layer and its backups are replicated across availability zones in the primary region, so a single datacentre failure does not take the database, and the application behind it, offline.

    14 min
  21. 21
    Site Reliability AZURE

    Enable soft delete and a sufficient retention window for storage

    One capability across blobs and containers: make sure that an accidental or malicious delete, or a bad overwrite, can be undone for at least a week, rather than being instant and permanent the moment it happens.

    13 min
  22. 22
    Site Reliability AZURE

    Add redundant Traffic Manager endpoints for failover

    One capability: make sure every Traffic Manager profile has more than one healthy endpoint, ideally in different regions, so that when one endpoint goes offline the profile fails over instead of taking the application down with it.

    13 min
  23. 23
    Site Reliability AZURE

    Spread virtual machines across availability zones

    One capability across every region that has them: make sure a workload that has to stay up does not sit on a single virtual machine in a single zone, so a datacentre fault takes out one zone, not the service.

    14 min
  24. 24
    Site Reliability AZURE

    Run scale sets as zone-redundant for fault tolerance

    One capability across every Virtual Machine Scale Set in the estate: make sure the instances are spread across multiple availability zones, so a single instance failure or a whole-zone outage is absorbed automatically instead of taking the workload down.

    14 min
  25. 25
    Site Reliability AZURE

    Replicate storage accounts across availability zones

    One reliability capability across Blob, File, Table and Queue: move accounts off locally redundant storage so their data is written synchronously across three availability zones and stays readable and writable when one zone goes dark.

    14 min