Azure Service Level Agreements (SLA)

The Service Level Agreement (SLA) describes Microsoft’s commitments for uptime and connectivity. A summary of SLA for individual Azure services is presented below, based on official Microsoft documentation (https://azure.microsoft.com/en-us/support/legal/sla/). A detailed list of the SLA of all Microsoft Online services can be found in a single document available for download at: http://www.microsoftvolumelicensing.com/DocumentSearch.aspx?Mode=3&DocumentTypeId=37

Compute

Virtual Machines

  • For all Virtual Machines that have two or more instances deployed in the same Availability Set, we guarantee you will have Virtual Machine Connectivity to at least one instance at least 99.95% of the time.
  • For any Single Instance Virtual Machine using premium storage for all Operating System Disks and Data Disks, we guarantee you will have Virtual Machine Connectivity of at least 99.9%.

What happens with single-instance VMs? 

Over the last few months, Microsoft have done extensive work to improve availability of the Azure infrastructure, including innovative machine-learning to predict failing hardware early and offering premium storage to help improve reliability and performance of attached disks. Microsoft have announced a 99.9% single-instance availability SLA to better support applications that cannot easily scale beyond single VMs. To qualify for the single instance virtual machine SLA, all storage disks attached to the VM must be using premium storage, which offers this high level of availability and performance with up to 80,000 IOPS and 2,000 MBps of disk throughput. In addition to this new availability commitment, customers can continue to build for multi-machine high availability by having two or more VMs deployed in the same Availability Set or by utilizing VM Scale Sets which both provide machine isolation, network isolation, and power unit isolation across multiple virtual machines.

More details about VM SLA can be found at https://azure.microsoft.com/en-us/support/legal/sla/virtual-machines/v1_6/ 

Virtual Machine Scale Sets

Virtual Machine Scale Sets is a free service, therefore, it does not have a financially backed SLA itself. However, if the Virtual Machine Scale Sets includes Virtual Machines in at least 2 Fault Domains, the availability of the underlying Virtual Machines SLA for two or more instances applies. If the scale set contains a single Virtual Machine, the availability for a Single Instance Virtual Machine applies.

App Service

We guarantee that Apps running in a customer subscription will be available 99.95% of the time. No SLA is provided for Apps under either the Free or Shared tiers.

Cloud Services

For Cloud Services, we guarantee that when you deploy two or more role instances in different Update Domains, at least one role instance will have Role Instance Connectivity at least 99.95% of the time.

Functions

For Function Apps running on App Service Plans we guarantee that the associated Functions compute will be available 99.95% of the time. No SLA is provided for Functions Apps running under Consumption Plans.

Azure Container Service (AKS)

Azure Container Service is a free service, therefore, it does not have a financially backed SLA itself. The availability of Azure Container Service is based on the SLA of the underlying virtual machines used.

Batch

We guarantee at least 99.9% of the time, we will successfully process requests to perform operations against Batch accounts.

Service Fabric

Service Fabric is a free service, therefore, it does not have a financially backed SLA itself. The availability of your Service Fabric cluster is based on the SLA of the underlying virtual machines and storage resources used.

Networking

Load Balancer

We guarantee that a Load Balanced Endpoint using Azure Standard Load Balancer, serving two or more Healthy Virtual Machine Instances, will be available 99.99% of the time. Basic Load Balancer is excluded from this SLA.

Application Gateway

We guarantee that each Application Gateway Cloud Service having two or more medium or larger instances will be available at least 99.95% of the time.

VPN Gateway

We guarantee 99.9% availability for each Basic Gateway for VPN or Basic Gateway for ExpressRoute.

We guarantee 99.95% availability for each Standard, High Performance, VpnGw1, VpnGw2, VpnGw3 Gateway for VPN.

We guarantee 99.95% availability for each Standard, High Performance, Ultra Performance Gateway for ExpressRoute.

Azure DNS

We guarantee that valid DNS requests will receive a response from at least one Azure DNS name server at least 99.99% of the time.

CDN

We guarantee that at least 99.9% of the time CDN will respond to client requests and deliver the requested content without error. We will review and accept data from any commercially reasonable independent measurement system that you choose to monitor your content. You must select a set of agents from the measurement system’s list of standard agents that are generally available and represent at least five geographically diverse locations in major worldwide metropolitan areas (excluding PR of China).

Traffic Manager

We guarantee that DNS queries will receive a valid response from at least one of our Azure Traffic Manager name server clusters at least 99.99% of the time.

Express Route

We guarantee a minimum of 99.95% ExpressRoute Dedicated Circuit availability.

Network Watcher

We guarantee that 99.9% of the time Network Diagnostic Tools will successfully execute and return a response.

Storage

Storage

  • We guarantee that at least 99.99% (99.9% for Cool Access Tier) of the time, we will successfully process requests to read data from Read Access-Geo Redundant Storage (RA-GRS) Accounts, provided that failed attempts to read data from the primary region are retried on the secondary region.
  • We guarantee that at least 99.9% (99% for Cool Access Tier) of the time, we will successfully process requests to read data from Locally Redundant Storage (LRS), Zone Redundant Storage (ZRS), and Geo Redundant Storage (GRS) Accounts.
  • We guarantee that at least 99.9% (99% for Cool Access Tier) of the time, we will successfully process requests to write data to Locally Redundant Storage (LRS), Zone Redundant Storage (ZRS), and Geo Redundant Storage (GRS) Accounts and Read Access-Geo Redundant Storage (RA-GRS) Accounts.

Managed Disks

Managed Disks does not have a financially backed SLA itself. The availability of Managed Disks is based on the SLA of the underlying storage used and virtual machine to which it is attached.

Data Lake Store

We guarantee that Data Lake Store will be available at least 99.9% of the time.

StorSimple

  • We guarantee at least 99.9% availability of the Backup, Cloud Tiering, and Restore functionality of the Azure StorSimple service.
  • We guarantee at least 99.9% of the time we will successfully process requests to the Azure StorSimple Data Manager.

Backup

We guarantee at least 99.9% availability of the backup and restore functionality of the Azure Backup service.

Site Recovery

  • For each Protected Instance configured for On-Premises-to-On-Premises Failover, we guarantee at least 99.9% availability of the Site Recovery service. Availability is calculated over a monthly billing cycle.
  • For each Protected Instance configured for On-Premises-to-Azure planned and unplanned Failover, we guarantee a two-hour Recovery Time Objective.

Web and Mobile

Logic Apps

We guarantee that Logic Apps running in a customer subscription will be available 99.9% of the time.

Media Services

  • For Media Services Encoding, we guarantee 99.9% availability of REST API transactions.
  • For Streaming, we will successfully service requests with a 99.9% availability guarantee for existing media content when at least one Streaming Unit is purchased.
  • For Live Channels, we guarantee that running Channels will have external connectivity at least 99.9% of the time.
  • For Content Protection, we guarantee that we will successfully fulfill key requests at least 99.9% of the time.
  • For Indexer, we will successfully service Indexer Task requests processed with an Encoding Reserved Unit 99.9% of the time.

We guarantee at least 99.9% availability for index query requests when an Azure Search Service Instance is configured with two or more replicas, and index update requests when an Azure Search Service Instance is configured with three or more replicas. No SLA is provided for the Free tier.

API Management

  • We guarantee that API Management Service instances running in the Basic, Standard and Premium tiers will respond to requests to perform operations at least 99.9% of the time. No SLA is provided for the Developer tier of the API Management Service.

Notification Hubs

We guarantee that at least 99.9% of the time, applications will be able to send notifications or perform registration management operations with respect to a Notification Hub. No SLA is provided for the Free tier.

 

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